MOAR! Monsters Know What They're Doing

MOAR! Monsters Know What They’re Doing

Keith Ammann

Author of

The Monsters Know What They’re Doing

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INTRODUCTION

Greetings, reader! If you’ve picked up this book, you’re probably already familiar with The Monsters Know What They’re Doing: Combat Tactics for Dungeon Masters, my guide to applying the traits and features of fifth edition Dungeons & Dragon monsters in combat encounters, or with the blog it was born out of. This book builds on the material of the first book, examining the stat blocks of more than two hundred fifty new creatures and non-player characters for clues as to how they’ll behave in combat. Like The Monsters Know What They’re Doing, MOAR! Monsters Know What They’re Doing is not a substitute for the official D&D books in which these adversaries appear, but rather a supplement to them; you’ll need to have those books to get any use out of this one.

In addition to these analyses, MOAR! Monsters includes my thoughts on combat-adjacent topics, such as how different types of monsters fight in tandem, how to run monsters that are smarter than your player characters (and, perhaps, even smarter than you), how to handle the tricky spells darkness and counterspell, and the astonishingly controversial optional flanking rule. Finally, I present to you something that a lot of readers have been requesting for a long time: recommendations on running archfiends.

This book cites official D&D publications over and over, in particular the three fifth edition core books and the two books that the monsters herein are drawn from, Volo’s Guide to Monsters and Mordenkainen’s Tome of Foes. In the interest of brevity, I refer to these latter two books throughout this work as Volo’s and Mordenkainen’s (which are more pleasing to my eye than the abbreviations often used online, VGtM and MToF). Also, I cite chapters and sections of the Dungeon Master’s Guide and the Player’s Handbook rather than page numbers, because page numbers can change from printing to printing.

Since I refer to it so many times, I use Targets in Areas as a short-form reference to the Targets in Areas of Effect table in the Dungeon Master’s Guide, chapter 8, Adjudicating Areas of Effect.

Finally, next to each section heading is a (V) or an (M), indicating whether the monster(s) in that section are found in Volo’s or Mordenkainen’s, with two exceptions. Lesser Demons contains fiends from both books, and I indicate the source of each one in the section text. Scouts and Spies has no such indication, because these NPCs—which, in a regrettable oversight, were left out of The Monsters Know What They’re Doing—are found in the Monster Manual, appendix B.

HOW TO ANALYZE A STAT BLOCK

In The Monsters Know What They’re Doing: Combat Tactics for Dungeon Masters, I discuss the premises behind my analyses in the section Why These Tactics? (1–4). However, that section, by itself, doesn’t provide a step-by-step tour through my whole process, and I’ve often been asked to discuss it in more detail. Also, no matter how many of these books I write or how long I can keep my blog going, there will always be monsters—in published adventures I haven’t bought yet, in third-party supplements, and so forth—that I won’t have analyzed in time for your game. So while I greatly enjoy supplying you with fish, let me give you an overview of how to catch them yourself.

As a case study, here’s a homebrew monster stat block:

BIN’AZG

Large monstrosity, neutral evil

Armor Class 16 (natural armor)

Hit Points 136 (21d10 + 21)

Speed 30 ft, burrowing 10 ft, climbing 30 ft

Str 20 (+5), Dex 16 (+3), Con 12 (+1), Int 8 (-1), Wis 11 (+0), Cha 10 (+0)

Saving Throws Dex +8

Skills Perception +5, Stealth +8

Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks

Senses blindsight 60 ft (blind beyond this radius), passive Perception 15

Languages understands Undercommon but does not speak

Challenge CR 13 (10,000 XP)

Keen Hearing and Smell. The bin’azg has advantage on Wisdom (Perception) checks that rely on hearing or smell.

Spider Climb. The bin’azg can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Spindly. The bin’azg can squeeze through a space as narrow as 21/2 feet wide.

Too Many Legs. When the bin’azg has less than 15 feet of either horizontal or vertical clearance, its walking and climbing speeds are increased to 50 feet.

ACTIONS

Multiattack. The bin’azg uses Terrify, then makes a Barbed Claw or Smashing Claw attack.

Bite. Melee Weapon Attack: +10 to hit, reach 5 ft, one target. Hit: 11 (2d4 + 6) piercing damage plus 14 (4d6) acid damage.

Barbed Claw. Melee Weapon Attack: +10 to hit, reach 10 ft, one target. Hit: 17 (2d10 + 6) piercing damage, and the target is grappled (escape DC 14). When a target creature that is not an undead or a construct escapes the grapple, it must make a DC 17 Constitution saving throw. On a failed save, the creature takes 5 (2d4) slashing damage, then loses 5 (2d4) hp at the start of each of its turns due to a bleeding wound. Any creature can take an action to stanch the wound with a successful DC 12 Wisdom (Medicine) check. The wound also closes if the target receives magical healing. The bin’azg has two barbed claws, each of which can grapple one target.

Smashing Claw. Melee Weapon Attack: +10 to hit, reach 10 ft, one target. Hit: 13 (2d6 + 6) bludgeoning damage, and the target must succeed on a DC 14 Constitution saving throw or be stunned for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Terrify (Recharge 5–6). Every creature within 60 feet that can see the bin’azg must make a DC 13 Wisdom saving throw. On a failed save, a creature is frightened for 1 minute. If the saving throw fails by 5 or more, the target is also incapacitated, unless it is immune to the frightened condition. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature’s saving throw is successful or the effect ends for it, the creature is immune to the bin’azg’s Terrify for the next 24 hours.

LEGENDARY ACTIONS

The bin’azg can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The bin’azg regains spent legendary actions at the start of its turn.

Chow Down. The bin’azg makes a Bite attack against a grappled or stunned opponent.

Detect. The bin’azg makes a Wisdom (Perception) check.

Spring (Costs 2 Actions). The bin’azg moves up to its speed toward a hostile creature, then makes one Barbed Claw or Smashing Claw attack. This movement is not slowed by difficult terrain. The bin’azg cannot use this legendary action while squeezing through a space.

Hundreds of years ago, a crew of mountain dwarf miners returned from a dig, hollow-eyed and shaken, telling of a nightmarish encounter: a creature with too many legs which pursued them with terrifying speed through the tunnels they had dug. Several of their number were so frightened by the creature that they could barely stir themselves to run. Those who made it back swore that the creature had no eyes in its spiderlike head yet seemed to know exactly where they were. They named it Bin’azg, the Eyeless, and never ventured again into the tunnels where they had found it. For years they believed it was the only one of its kind—until reports came from other dwarven citadels of monsters that fit the same description.

Like spiders, bin’azg have dual-segmented bodies, with their heads fused to their thoraxes. Accounts vary on the number of legs they possess, from as few as eight to as many as eighteen, but it is consistently reported that they also have two pairs of claw-tipped arms, one pair for impaling prey on harpoonlike barbs and one pair for clubbing prey with hammerlike blows. Witnesses also agree that bin’azg have no visible eyes yet seem to track other creatures with uncanny accuracy by sound or smell, and that they prefer to immobilize their prey before devouring it.

Bin’azg are never seen aboveground and seem to strongly prefer tunnels to open caverns. The radial configuration of their legs allows them to propel themselves rapidly through tunnels by making simultaneous contact with both floor and ceiling or with walls on either side. Dwarves who have escaped encounters with them observe that bin’azg are easier to outrun when they cannot orient their legs in opposite directions as they move.

FLAVOR TEXT

The lore accompanying a monster’s stat block is often the last thing I look at, unless I’m having trouble making sense of the stat block. My fundamental premise is that eons of existing in the D&D universe have allowed creatures, as species, to develop instinctive behaviors that make the highest and best use of the game mechanics behind their traits and features (with a few exceptions, such as undead compulsions and the mechanistic behavior of constructs). Once I’ve determined what kinds of behaviors the contents of a stat block imply in and of themselves, then I turn to the flavor text for context, clarification, and nuance. I find that reading this text after looking at the stat block, rather than before, helps me recognize further implications of the features I’ve just looked at—adding to the number of tactical possibilities I’m considering. Conversely, if I read the flavor text first, I’m more likely to let it override my own insights—limiting the possibilities.

However, there is one relevant quality you’ll sometimes find in the flavor text that may not have a proxy in the stat block: fanaticism. Monsters and non-player characters that engage in combat for ideological rather than instinctual reasons are more likely to fight to the death.

The bin’azg is a creature of my own creation, and it acts exactly as I want it to act, so there’s no inconsistency between its flavor text and its stat block. Not all flavor text is as consistent. An example of flavor text highly consistent with the features in the accompanying stat block is that of the steel predator in Mordenkainen’s, which describes it as a merciless machine with one purpose: to locate and kill its target regardless of distance and obstacles. An example of flavor text less consistent with the accompanying stat block is that of the marut, also in Mordenkainen’s, which implies that only one marut is ever bound to enforce a given contract, even though multiple maruts may sometimes be required to retrieve all the parties who’ve violated it.

MONSTER SIZE, TYPE, AND ALIGNMENT

Size often correlates inversely with numbers: Tiny and Small monsters are more likely to swarm their opponents, while Huge and Gargantuan monsters are usually loners. When monsters depend on numbers to overwhelm their opponents, the decision to retreat is often made on a group basis rather than individually, as a function of what fraction of their total force is seriously injured or slain. Especially if they have a feature, such as Pack Tactics, that grants them bonuses when attacking alongside others of their kind, such monsters will often abort an attack when they no longer outnumber their opponents by at least two to one—or even three to one, depending on relative strength.

A monster’s type, as I explain in The Monsters Know What They’re Doing (What Monsters Want, 7–12), is a reliable predictor of its goals and priorities; whatever its tactics, it uses them in service of these. Alignment indicates a monster’s usual initial attitude: Good creatures tend to be friendly by default, neutral creatures indifferent, and evil creatures hostile. Note, however, that lawful creatures may be less friendly and more hostile toward characters behaving chaotically, and vice versa. (Calling unaligned beasts friendly or hostile anthropomorphizes them. They’re beasts; they do beast things for beast reasons.)

The bin’azg is a Large monstrosity, neutral evil. It’s a self-interested, territorial hunter; it hunts alone, and it’s hostile to other creatures it encounters by default. It also doesn’t stop chomping on a target who’s reduced to 0 hp. It came to eat; it’s gonna eat. If attackers interrupt its meal, however, it does try to drive them off, dragging any grappled prey along with it wherever it goes.

ARMOR CLASS, HIT POINTS, AND SPEED

The stats in this section have one thing in common: They all influence when and how a monster runs away. Higher Armor Classes (above 15) make Dodging a feasible damage-reducing action to take while retreating; a speed higher than 30 feet strongly favors Dashing. An alternative movement mode (burrowing, climbing, flying, or swimming) allows a monster to flee where its pursuers can’t go. Starting hit points determine the thresholds for light wounds (It felt that), moderate wounds (It knows you’re a threat now), and serious wounds (Its survival is at stake). I set these bars at 10, 30, and 60 percent of starting hit points, so that a monster with 70 percent of its starting hit points or less is moderately wounded, and one with 40 percent or less is seriously wounded.

Natural predators, which dislike prey that fights back, tend to break off their attacks when they’re only moderately wounded, as do monsters and NPCs with a heightened sense of self-preservation. More belligerent monsters and NPCs retreat when they’re seriously wounded, and fanatics don’t retreat at all—or wait to retreat until they’re seriously wounded, if they otherwise would retreat when only moderately wounded. I prefer these more nuanced figures to the 50 percent guideline given in the Player’s Handbook (chapter 9, Describing the Effects of Damage), which strikes me as not enough damage to induce more belligerent monsters to run away and superfluous for more cautious ones.

The higher a monster’s Armor Class, the more willing it is to risk an opportunity attack by leaving an opponent’s reach without Disengaging. The lower the Armor Class, the less willing.

If a monster’s base speed is lower than its speed in an alternative movement mode, it favors the alternative mode. For example, a monster with a 30-foot speed but a 40-foot flying speed prefers to stay in the air; one with a 20-foot speed but a 30-foot swimming speed prefers to stay in the water.

With 136 hp, the bin’azg is moderately wounded when reduced to 95 hp or fewer and seriously wounded when reduced to 54 hp or fewer. As a predatory creature, the bin’azg might normally be expected to flee when only moderately wounded: Predators favor weak prey over prey that fights back. However, its nature as a monstrosity and its evil alignment drive it to keep fighting until it’s seriously wounded before running away. Its high speed favors Disengaging when retreating, but it may not be smart enough to know how; its Armor Class is high enough that Dodging as it retreats is slightly preferable to Dashing, unless it’s being pursued by an opponent with Extra Attack.

ABILITY CONTOURS

Every set of ability scores has its peaks and valleys. Every monster naturally plays to its strengths and is held back by its weaknesses. Thus, the highs and lows of a monster’s ability scores are crucial to understanding its fighting style: how it attacks and how it defends.

A monster’s primary offensive ability, the one that determines its preferred mode of attack, can be Strength, Dexterity, Intelligence, Wisdom, or Charisma. It’s usually the highest of these, though not always. If a monster’s POA is Strength, it favors brute-force melee attacks. If its POA is Dexterity, it favors finesse or ranged attacks. If its POA is Intelligence or Wisdom, it favors spellcasting. If its POA is Charisma, it may also favor spellcasting, or—if it’s proficient in one or more social skills—it may be more inclined to talk than fight.

A monster’s primary defensive ability is Dexterity or Constitution.I

If a monster’s PDA is Constitution, it’s happy to engage in melee. If a monster’s PDA is Dexterity, it prefers to keep its melee engagements short—or to keep its distance.

The combination of POA and PDA produces certain characteristic types, such as the brute (Strength + Con), the shock attacker (Strength + Dex, or Dex + Dex without a ranged attack), the sniper (Dex + Dex with a ranged attack), the skirmisher (Dex + Con), the long-range spellcaster (mental ability + Dex), and the war caster or support caster (mental ability + Con). It’s possible to imagine other profiles (e.g., the finesse mystic hexblade, a mental ability + Dex duelist that employs a weapon rather than spells), but the aforementioned encompass the overwhelming number of published monsters.

Intelligence and Wisdom also influence how analytical and intuitive a monster is with respect to the fight it’s in, how well it adapts to unexpected circumstances, and how accurately it assesses threats. For more specifics on these, see The Monsters Know What They’re Doing, Why These Tactics? (2–3).

The bin’azg’s highest ability scores are Strength and Dexterity, making it a shock attacker: a big damage dealer that strikes hard, tries to end the fight quickly, and retreats if it can’t. If it hasn’t managed to take out at least one opponent after three rounds of combat, or if its foes are still trying to fight it off at that point, it withdraws—perhaps to attack again later, perhaps not. Its Intelligence is low-average, indicating a lack of sophistication in tactics but some ability to adapt to circumstances. Its Wisdom is also middling: It has a normal self-preservation instinct, but it’s indiscriminate in its target selection, tending to attack whoever or whatever is closest.

RESISTANCES, IMMUNITIES, AND VULNERABILITIES

These generally don’t influence a monster’s tactics directly; what they influence instead is how great a threat a monster considers a particular foe to be. A monster that’s resistant or immune to bludgeoning, piercing, and slashing damage from non-magical sources is much more blasé about getting whaled on by a melee fighter with a mundane weapon than one without such resistance or immunity, and it’s also more willing to risk an opportunity attack by moving out of its opponent’s reach. Smarter monsters recognize opponents who deal damage they’re more susceptible to as targets that need to be taken care of first. Stupider ones don’t think in those terms, but they can tell more ouch from less ouch, and they know that more ouch is something to avoid.

Although it’s usually found further down in the stat block, among a monster’s passive traits, consider Magic Resistance to be in the same category as these.

With resistance to physical damage from normal weapons, a bin’azg expects little resistance and is surprised to meet opposition that strikes back with enchanted weapons or other magical damage. It may turn tail sooner if it takes a lot of these kinds of damage at once.

SENSES

Any monster with a special sense that lets it see under certain adverse conditions prefers to fight in those conditions. Monsters with darkvision attack in dim light or darkness rather than broad daylight. Monsters with blindsight hunt in total obscurity. Monsters with tremorsense, especially if they can also burrow, lurk underground until they feel the movement of prey.

With blindsight and Keen Hearing and Smell, a bin’azg waits quietly in subterranean darkness until it hears or smells potential prey. It creeps quietly toward its targets until it’s about 60 feet away, then uses its speed, combined with a long-reaching claw attack, to strike with surprise.

SKILL PROFICIENCIES

Certain skill proficiencies signify particular types of behavior. One of the most common combinations is Perception and Stealth: Together, these proficiencies indicate an ambush attacker that lies in wait until it detects prey, then strikes, hoping to surprise its foes and also, perhaps, gain advantage on its first attack roll. Stealth proficiency plus a trait that allows a monster to Hide mid-combat as a bonus action, such as Nimble Escape, indicates reliance on repeated hit-and-run attacks. Athletics proficiency may indicate a predilection for grappling; Acrobatics suggests that a monster is hard to pin down by such means. Survival proficiency often indicates a predator that tracks prey by sign or scent, and if a chase ensues with such a monster in pursuit, it may continue to go after its quarry even after they believe themselves to have escaped. Deception, Intimidation, and Persuasion are all different approaches to parley; a monster proficient in one or more of them sees and seizes opportunities to achieve its goals through conversation rather than combat. Bring Insight proficiency into the mix, and you add an extra level of shrewdness.

With proficiency in Perception and Stealth, the bin’azg is a classic ambush attacker.

PASSIVE TRAITS

The sections above all lay the foundation of a monster’s tactical behavior. This section and those that follow are the edifice.

Now that you know a monster’s basic approach to combat and whom it sees as its most important targets, you can determine the specific techniques it uses by looking at its passive traits (which often include available bonus actions), actions, reactions, and spellcasting ability, both learned and innate. In particular, the traits in this section should give you an idea of the monster’s style, as well as how it expresses that style through one or more game mechanics. Keep an eye out for anything that directly confers advantage or imposes disadvantage, that sets a condition (especially blinded, charmed, paralyzed, prone, restrained, or stunned), or that can be used in combination with some other trait. When it comes to combos, pay attention to sequence: Often, traits work together in one order but not in another. Ask yourself when during its turn a monster should use a bonus action to gain the most benefit from it.

The bin’azg’s Too Many Legs and Spindly traits, together with its blindsight, make underground tunnels its ideal hunting ground, but Spider Climb lets it lurk in surprising places underground as well. The speed boost of Too Many Legs allows it to appear and attack seemingly from out of nowhere, and the combination of Too Many Legs and Spindly lets it aggressively pursue fleeing prey almost anywhere it tries to run. Keen Hearing and Smell gives the bin’azg a way to detect prey beyond the range of its blindsight.

SPELLCASTING

Analyzing spellcasting monsters can be daunting because of the number of options that have to be weighed against one another. There’s no easy answer but to slog through it.

Innate Spellcasting spells are either at will or limited to a specific number of uses per day. At-will spells are ones that a monster casts anytime they give it a leg up. Remember, though, that at-will spells aren’t free: They cost time, and therefore you have to decide whether the benefits they offer are worth the opportunity cost of casting them. However, if they provide a lasting benefit—and especially if they don’t require concentration to sustain, or can be cast as bonus actions—they probably are. A spell limited to one use per day is meant to do a specific thing in a specific situation; figure out what that thing and that situation are. A spell limited to three uses per day can be employed more opportunistically, whenever appropriate circumstances present themselves, but they’re not as all-purpose as at-will spells are and should be cast more mindfully.

For further discussion of spellcasting monsters, see Magical Specialists, page 139–45

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The bin’azg doesn’t cast spells, even innately, so there’s no decision to make here.

ACTIONS AND REACTIONS

The actions included in a stat block are mostly attacks; those that aren’t attacks are mostly abilities that set up attacks. Actions that must recharge before they can be used again are especially powerful—their use is rationed!—which usually means that a monster wants to use them whenever they’re available. But there’s an exception: An action that recharges only on a roll of 6 is one that you must assume the monster will get to use only once during a combat encounter. It has to strike when the iron is hot, which may or may not be at the outset of combat. Figure out what likely circumstances are necessary to maximize the effectiveness of that action. If by chance the monster does roll that 6 and gets to take the action a second time, it’s much less fussy about preconditions.

A monster’s ability contour tells you whether it favors melee attacks over ranged attacks or vice versa, but when weighing attack actions of the same type against one another, and also when weighing attack actions against actions whose effects require saving throws to resist, it’s important to know how to calculate average and expected damage. By average damage, I mean the average amount of damage an attack deals on a hit. By expected damage, I mean average damage times the probability of hitting, which I usually base on AC 15 at lower levels of play, AC 18 at higher levels. Since attack actions of the same type nearly always have the same chance to hit, it’s simplest to compare their average damage—although I prefer to calculate it myself, rather than pull it directly from the stat block, in order to know the exact values before rounding.II

However, when you’re comparing apples with oranges, you need to know how much damage each action can be expected to deal.

To calculate the expected damage of a saving throw ability, I generally assume a 50 percent chance of success, since monster saving throw DCs tend to scale with their challenge ratings as PC saving throw modifiers scale with their levels. Since most damage-dealing actions that require saving throws deal half damage on a successful save, expected damage usually works out to three-fourths the average damage on a failed save (50 percent chance of full damage plus 50 percent chance of half damage).

Figuring the impact of a saving throw ability that doesn’t deal damage directly but rather imposes a condition or increases the likelihood of success on another action requires gaming out the outcomes of the various possible sequences. You won’t get far down this road without a grounding in probability math, which I have neither the space nor the credentials to provide here. If you don’t have it, go with your gut and don’t worry about it—you’re not being graded.

When calculating the expected damage of an area-effect ability (including area-effect spells), remember to multiply the expected damage against one target by the number of expected targets, as determined per Targets in Areas. Also, remember that the value of a Multiattack action equals the total expected damage of all the actions it comprises.

Of the bin’azg’s three attack actions, Bite deals the most damage but also has only 5 feet of reach, while the claw attacks both have 10 feet of reach. Barbed Claw deals more raw damage than Smashing Claw, but Smashing Claw can impose the stunned condition, which adds value since it incapacitates the target and confers advantage on attack rolls against them. Terrify is a 5–6 recharge ability that’s also part of the bin’azg’s Multiattack, so naturally it will seek to combine Terrify with a claw attack whenever the former action is available, until all prospective targets have gained immunity to it. Both claw attacks have the potential to immobilize opponents, making them easier targets for Bite. Thus, a reasonable attack sequence is Terrify/Barbed Claw, followed on subsequent turns by Smashing Claw if the grappled target escapes and Bite (or its other Barbed Claw against a second opponent) if they remain grappled.

LEGENDARY AND LAIR ACTIONS

Actions that a monster can take on other creatures’ turns make lovely retorts to whatever those creatures have just done—but they can also allow a monster to underline the irrelevance of whatever those creatures have just done by using a legendary action against someone else, or by not bothering to use one at all. Remember that legendary actions, like Readied attacks, must be used where the monster stands (or hovers), unless they specifically include movement. Set common-sense criteria for using each one, with stricter criteria for options that cost two or three legendary actions. Don’t skimp on legendary actions: Your monster’s challenge rating depends on them.

Lair actions, which occur on initiative count 20, give a monster even more home-field advantage than it already possesses. They’re often more strategic in nature, allowing a monster to change the conditions of combat in its favor, control movement, or divide opponents. It’s rarely difficult to figure out what kinds of opponents these actions are meant to thwart. When a lair action does nothing but deal direct damage, it’s usually a default to employ when there’s no particular need to use some other lair action. Note that a monster with lair actions is often—but not always—prohibited from using the same one twice in a row.

The bin’azg doesn’t exercise much care in choosing its targets—it tends to attack whatever’s nearest—but if all its prospective targets are hidden beyond the range of its blindsight, it can use its Detect legendary action to try to sniff one out. Spring lets it quickly close the distance between itself and the nearest fleeing opponent, and Chow Down simply deals more of that massive Bite damage. The dwarves who dug this critter up had good reason to be scared.

I

. Wisdom is technically a defensive ability as well, but one that defends only against social and mental manipulation, not against bodily damage. It would only be considered a monster’s PDA if its Wisdom were significantly higher than both its Dexterity and its Constitution. Generally, such a monster would avoid combat altogether; if it did fight, it would do so only if it enjoyed a major numerical advantage.

II

. In fifth edition D&D play, the general rule is to round fractions down. In this book, while analyzing damage probabilistically, I round fractions to the nearest whole number, with one-half rounded to the nearest even whole number.

THE MONSTERS

HUMANOIDS

XVARTS (V)

Xvarts are difficult to devise tactics for, because their ability scores, their features, and their flavor text in Volo’s all seem to be at odds with one another. Their ability scores suggest Dexterity-focused sniping and shock attacks. Their Overbearing Pack feature suggests a reliance on shoving opponents prone, presumably to be followed up with melee attacks (both of which depend on Strength). And the flavor text states that they attack primarily to abduct, which implies either grappling targets or knocking them unconscious.

There is a solution, but it’s tricky.

Xvarts move at the normal humanoid speed of 30 feet per round. Their Strength is low, and their Constitution merely average, so they’re averse to melee slugfests. Xvarts necessarily seek strength in numbers—and allies, specifically giant rats and giant bats. Giant rats make particularly good allies for xvarts, because of their Pack Tactics feature; giant bats, however, are tougher, with a slightly higher challenge rating. A xvart encounter should include, at a minimum, two xvarts per player character, plus an animal ally for every two xvarts.

Xvarts are neither smart nor wise. They have no ability to adapt if their favored strategy doesn’t work, and they may not be particularly quick to notice that it isn’t working. However, unlike the usual low-Wisdom monster, which waits too long to run away, xvarts are cowardly; if anything, they’ll run away prematurely from encounters that favor them. The Low Cunning feature gives them Disengage as a bonus action, but this represents instinctive evasive ability, not discipline.

So how do you create an effective kidnapper out of a low-Strength creature without proficiency in Athletics? By building a strategy around the distinctive Overbearing Pack feature, which gives a xvart advantage on a shoving attack as long as it has an ally—in this case, a giant rat—within 5 feet of the target. The xvart’s Strength modifier is an unimpressive -1, but advantage jacks this up to an effective +3 or +4, allowing it to compete with stronger or nimbler PCs.

Xvarts have darkvision and proficiency in Stealth. By attacking only in twilight or (if the party contains PCs who have darkvision themselves) at night, xvarts can minimize their chance of being seen before they attack. They send their animal allies out first (giant rats have darkvision, and giant bats have blindsight, so visibility isn’t a problem) to distract their enemies, then follow up with attacks of their own.

Let’s say we start with giant rats. The xvarts send in the rats, which lack Stealth proficiency, so they attack in pairs to gain advantage from Pack Tactics. The xvarts wait until their enemies are engaged, then move in and attack to shove their victims prone, intending to follow up by grappling so that they can’t get back up.

Observant readers will have noticed that, based on my encounter building guidelines, there won’t be enough animal allies to engage every enemy. The rats and bats are for use against the front line. The xvarts themselves, which are numerous, can take care of the rest of their opponents by double- and triple-teaming them.

Example: A level 1 party consists of Áine, a wizard; Daria, a marksman ranger; George, a sword-wielding rogue; Lennie, a front-line fighter; and Tolmac, a druid. These five PCs are ambushed at night by a pack of ten xvarts, accompanied by five giant rats. When the attack is launched, three of the rats swarm Lennie, while the other two go after either George or Tolmac—let’s say George. (Sending rats to attack a druid would be a mistake, but then again, it’s exactly the sort of mistake a dimwitted xvart might make. Don’t overthink it. The xvarts pick George because George has a sword, while Tolmac just has a big stick.)

Once the rats have engaged their foes, the xvarts move in: one against Lennie—nah, make it two, he’s pretty big; one against George; two against Áine; three against Daria, who looks a little tougher; and two against Tolmac. (Xvarts judge their opponents mainly on the basis of size, armor, and armament.) Taking advantage of low visibility and their targets’ distraction (Player’s Handbook, chapter 7, Hiding), they slink up to their targets and try to waylay them without being noticed before they strike. If a xvart is spotted as it approaches, it doesn’t attack; instead, it immediately runs for cover and tries to Hide again.

As I mentioned above, the xvarts’ first attack is a shoving attack, to knock their opponents prone. If two or more xvarts are attacking a single target and the first succeeds in knocking the target prone, the second immediately attacks to grapple. If the target isn’t grappled by the end of the turn, they’ll probably get right back up, which will scare the xvarts and cause them to run for cover.

If the target is grappled, the xvarts remain adjacent to one another as they drag the target off, the auxiliary xvart using the Help action to give advantage to the grappling xvart on its Strength (Athletics) checks, while menacing the victim with its shortsword. If there’s a third xvart (as against Daria above), it gives the victim a smack with its shortsword for good measure, aiming to knock them unconscious.

Additionally, as the Volo’s flavor text says, the xvarts throw nets or sacks over their grappled victims, since probability dictates that a strong victim will get lucky and break the grapple after a few rounds even if the xvarts have advantage on their rolls. You’ll have to use DM discretion and combine the restraining effect of the net (Player’s Handbook, chapter 5, Special Weapons) with the xvarts’ advantage on Strength (Athletics) checks to resist escape, or it will be too easy to get out. Even so, being restrained imposes disadvantage only on Dexterity checks, not on Strength checks, so in all likelihood, Lennie will still burst his bonds sooner or later—and that’s okay. Making things fair for the xvarts doesn’t mean making them unfair for the PCs.

Xvarts are team players by necessity, not by nature, and if one is moderately wounded (reduced to 4 hp or fewer), it runs off—using the Disengage bonus action, then the Dash action—and leaves its companions to their fate. Xvarts hauling a grappled or restrained enemy who breaks free also make a run for it, as do their companions, as soon as they notice. So do xvarts abandoned by their partners in the initial attack.

The presence of a xvart warlock changes the parameters of the encounter. For starters, xvart warlocks, if they leave their settlements, are usually leading expeditions in search of magical treasure, not sacrificial victims to abduct. In this scenario, the xvarts apportion and comport themselves differently: A giant rat attacks each target, then two xvarts attack that target normally with their shortswords (statistically superior, in terms of expected damage, to giving up one of those two attacks in order to try to knock the target prone). Then both xvarts Disengage (bonus action) and retreat 15 feet from their target; if the target pursues, it’s subject to an opportunity attack from the rat. Moderately wounded xvarts still run away, Disengaging (bonus action), then Dashing (action).

Meanwhile, the xvart warlock, fortified with mage armor, keeps its eyes peeled for enemies who are seriously wounded, whom it can finish off. The warlock always wants to try to get in the last blow, because Raxivort’s Blessing gives it 4 temporary hit points whenever it reduces an enemy to 0 hp.

The warlock has four offensive spells, two leveled (burning hands and scorching ray) and two cantrips (eldritch blast and poison spray).

Burning hands requires a Dexterity save to resist and deals 4d6 fire damage to each enemy in its area of effect who fails their save and half that to each enemy who succeeds; the warlock wants to make sure there are at least two (Targets in Areas). Thus, we’re looking at about 21 expected damage.

Scorching ray, on the other hand, is a ranged spell attack, and it does only half as much expected damage—but it’s good out to a range of 120 feet, as opposed to burning hands’ 15 feet.

Each of these spells costs a spell slot, of which the warlock has only two—and it wants to save one for either expeditious retreat or invisibility, its escape-hatch spells. Thus, it saves them for moments when it can finish off at least one of two opponents at close range or at least one of three at long range.

It has no limit on eldritch blast and poison spray, but neither of these can be expected to deal more than a few points of damage—in fact, if an enemy comes within 5 feet of the warlock, it’s going to take a swing with its scimitar rather than take a chance on poison spray. Poison spray tends not to work so great on the kinds of enemies who’ll charge a warlock.

Expeditious retreat and invisibility both require concentration, so the xvart warlock can cast one or the other but not both. It casts the former if its path of escape includes an abundance of cover, the latter if it has to run away across open terrain. Like other xvarts, the xvart warlock is a coward, and it takes to its heels when it’s only moderately wounded (reduced to 15 hp or fewer).

DERRO (M)

Derro are small humanoids native to the Underdark. Equal parts fearful and vicious, says Mordenkainen’s, [they] prey on those weaker than themselves, while giving simpering obeisance to any creatures they deem more powerful. You know the type: They believe absurdities, and they applaud atrocities.

With high Dexterity and above-average Constitution but merely average Strength, derro are skirmishers, but they’re not especially mobile ones. Their Intelligence is average, but their Wisdom, for some reason, is in the cellar. This mental ability contour is unusual; the reverse is far more common, especially since Wisdom supports the Perception skill. Not only are they easy to get the drop on, they also have an underdeveloped survival instinct, making them more likely to fight to the death. They are, however, proficient in Stealth, predisposing them toward an ambush strategy.

They have excellent darkvision and Sunlight Sensitivity, so they rarely venture aboveground for any reason, and absolutely never during the day. These traits combine with their innate paranoia to suggest an intense territoriality: Not only do they defend their turf viciously, they hardly ever leave it at all, except to try to conquer an adjoining sliver of new territory.

Derro have two weapon attacks, Hooked Spear and Light Crossbow. One option with the spear is to knock an enemy prone (presumably by hooking and tripping them), which would give any adjacent melee attacker advantage on a follow-up attack. However, a ranged attacker has disadvantage against a prone target, so this doesn’t help the crossbow-wielding derro at all. Even worse: It turns out, if you run the numbers, that even if the first derro in a group successfully hooks and trips an enemy, its allies nearly always deal less expected damage, despite having advantage on their attack rolls, than the group would do if all of them simply attacked to deal damage.

This holds true for any group of two to five derro. It takes six or more derro attacking a single opponent in melee for the advantage from hooking and tripping to produce an increase in overall damage, and at that threshold, it works only against unarmored, lightly armored, or moderately armored opponents.

Reflecting on this fact, I think the hook-and-trip should be considered an advanced derro tactic. Derro have a challenge rating of only 1/4, so you can throw them against even level 1 PCs. Against these PCs, they don’t appear in great enough numbers to do anything but stab. But once your PCs are up around level 5 and higher, they’re going to be fighting hordes of derro, not just patrols and platoons, and in that instance, the first in each group of attackers hooks and trips to try to give the rest advantage. (For the sanity of your players and yourself, use the Handling Mobs rule in chapter 8 of the Dungeon Master’s Guide, and figure that advantage gives +4 to hit.) Assuming they all share the same initiative count, derro wielding crossbows all shoot first, before any of their enemies fall prone, and then the derro with spears attack.

Alternatively, if you’re more interested in flavor than in optimization, always have the first derro in a group of three or more wielding spears attack to hook and trip! The average difference in damage is less than 1 point, and your players probably won’t do the math on the fly and realize that being flat on their prats doesn’t put them in any more danger than they were in standing up.

After all that, it seems almost anticlimactic to point out that the light crossbow deals significantly more damage than the spear—86 percent more, on average. So rather than divide up a derro unit between crossbowmen and spearmen, assume that every derro carries both a crossbow and a spear; that they prefer to use their crossbows over their spears; but that when an enemy rushes them, they switch, and so do their immediate neighbors. Also, if at all possible, they launch their first crossbow volley from hiding, to gain unseen attacker advantage.

Derro paranoia and low Wisdom mean they don’t flee when seriously wounded but rather keep on fighting until they’re down to 1 or 2 hp. At that point, the gravely wounded derro run, baiting out opportunity attacks—and their erstwhile allies seize that opening to retreat out of melee range themselves and go back to attacking with their higher-damage crossbows. If combat drags on beyond three rounds, all derro flee the scene, Dashing away. But this is simply a strategic retreat. They’ll gather some more allies, stalk their opponents, and ambush again as soon as they get the chance.

The Derro Madness sidebar in Mordenkainen’s is mainly a roleplaying guide, with little or no impact on derro tactics. Advantage on saving throws against being charmed and frightened doesn’t change much, since derro already have Magic Resistance; it adds only a small number of edge cases, such as being resistant to a Berserker barbarian’s Intimidating Presence. The effect of Insanity is already encapsulated by the derro’s pitiful Wisdom score, which scrambles its awareness of how much danger it’s in.

Derro savants are derro with sorcerous ability. Aside from having high Charisma and slightly below-average Strength, they have exactly the same ability contour as a regular derro. Because that below-average Strength makes them even less effective in melee, however, they always attack from range, and other derro run interference for them in case an enemy tries to close to melee distance.

Lightning bolt is the big gun in the derro savant’s arsenal, but it has the drawback of affecting only a narrow, straight line. Invisibility, however, gives the derro savant the freedom to position itself where it can cast a lightning bolt that nails four or more enemies, if they’re properly lined up. It’s most likely to get this chance if the battle has a well-defined front line. In a more all-over-the-place battle, there may never be a good opportunity to cast lightning bolt.

Normally, I’d say, the derro savant should use its 3rd-level spell slots for lightning bolt and nothing else. But I’d also say that because of the length of its area of effect, it’s practically wasted if cast against just one or two enemies. So what about, say, boosting chromatic orb with a 3rd-level spell slot? That would make it deal 5d8 damage (22, on average) against a single enemy with a ranged spell attack roll, vs. 8d6 damage (28, on average) against one or two enemies, with the burden on them to make a Dexterity saving throw, and half damage dealt even if they succeed. There’s no comparing the two. Chromatic orb falls far short.

Burning hands? At least that one requires a Dex save, deals half damage on a success, and can affect a second target, but even when boosted to 3rd level, the base damage is only 5d6 (17, on average). This one’s a self-defense measure for when the derro savant gets sacked, nothing more. As for sleep, it just doesn’t scale well. So save those 3rd-level spell slots, even if the opportunity to cast lightning bolt doesn’t seem to present itself. The derro savant holds out hope that the moment will come eventually, and when it does, it will be ready.

As for cantrips, the derro savant has two that deal damage: acid splash and ray of frost. Ray of frost is better, but neither is that great. The derro savant uses up its lightning bolts and chromatic orbs before resorting to cantrips. Spider climb is useful for casting from the safety of a high ceiling, escaping in a high-verticality environment, and not much else—and the derro savant is as unlikely to flee as any other derro. Sleep won’t be much use once the PCs are past level 4 or so, unless a significant number of them are seriously wounded. Then again, derro—even derro savants—are poor judges of the strength of their opposition, so a derro savant may unwittingly waste sleep on a group in which it will affect one target at most.

GRUNGS (V)

I have to hand it to Volo’s for giving us grungs, undisputed winners of the Most Adorable Evil Creature title, formerly held by kobolds.

Clearly based on poison arrow frogs, grungs are arboreal rainforest dwellers, tribal and territorial. In the latter respect, their behavior in groups therefore resembles that of lizardfolk, so I refer readers to my entry on them in The Monsters Know What They’re Doing (34–38). Grungs’ amphibian nature also invites comparison to bullywugs.

Lizardfolk are brutes, but grungs are low-Strength, high-Dexterity, high-Constitution skirmishers. Their low Strength means they’re going to be encountered in large numbers: no fewer than half a dozen at a time, I’d say. If they’re going to initiate an encounter against your PCs, rather than vice versa, they’ll have to outnumber the party at least three to one.

Grungs share the Amphibious and Standing Leap features with bullywugs. This means they’ll often be found in swampy areas, around rivers, and in other sorts of difficult terrain, which they can get around in easily by jumping. They’re quicker than bullywugs, though not as quick as most PCs, and since they can climb as well as jump, they use their proficiency in Stealth to hide in trees and drop on their enemies from above.

Grungs aren’t stupid. They have average Intelligence and Wisdom, so they’re not going to keep using a certain tactic if it’s not working, and they know when they’re beaten. Once they no longer outnumber their foes by at least two to one, or once a majority of them are seriously injured (reduced to 4 hp or fewer) or killed, they Dash off toward the heart of their territory.

Ordinary grungs wield daggers. Using them as a ranged weapon isn’t a completely absurd proposition, but their range is so poor that grungs can easily close with any enemy they could reasonably hit with a dagger and engage them in melee. Ideally, therefore, grungs would like to outnumber their opponents and surround them; they throw their daggers only if this isn’t an option.

Fighting grungs should be like fighting popcorn. Anytime an opponent lands a hit on a grung, the first thing it does on its next turn is jump away, either off into the undergrowth or up into a tree. Either way, it can then use its action to Hide, since its fellow grungs can keep whoever struck it occupied. Once it’s hidden, it maneuvers around until it can attack from hiding again. This assumes, of course, that the damage the grung took wasn’t enough to seriously wound it—in that case, it simply flees.

The Grung Poison variant suggests a variety of quasi-hallucinogenic side effects of failing the saving throw against grung poison. What’s not clear is whether these effects are meant to apply only to the toxin in the grung’s Poisonous Skin or the one on its dagger as well. If it includes the latter, an army of grung warriors will consist of green grungs, whose toxin limits a poisoned creature’s movement to climbing and standing jumps. Once an enemy is poisoned, the grungs stop attacking it and take it captive.

If you’re not using the Grung Poison variant, capture is still the grungs’ ultimate goal. Two or more grungs that have knocked an enemy out drag it back toward the heart of their territory; one alone can only move at a speed of 5 feet per turn if its burden weighs more than 105 pounds, and since it would be moving across difficult terrain (rainforest), that speed would be reduced to 2 feet per turn. (Jumping while carrying the dead weight of an unconscious abductee simply isn’t workable.) However, if enough of them are cooperating to manage the burden, the only applicable penalty is the terrain penalty, meaning they’ll move at 12 feet per turn. I’d also say the half-movement penalty for moving a conscious grappled enemy (which would further reduce their speed to 6 feet per turn) doesn’t apply if two or more of them are cooperating to carry them off.

The Poisonous Skin feature is an interesting one, because it explicitly describes what happens when another creature tries to grapple a grung but not what happens if a grung tries to grapple another creature. Should the same effect occur? I’d say yes, based on the phrase or otherwise comes into direct contact with the grung’s skin. This ruling aids the grungs in their efforts to kidnap trespassers.

In summary, here’s how I see a grung combat encounter playing out:

Green grung warriors hide in trees, scouting for trespassers. They attack when they outnumber the trespassers by three to one or more.

On their first turn, they leap down upon their (hopefully) surprised targets, attacking from hiding (advantage) with their daggers.

On their second turn, if they’ve taken a light or moderate hit (up to 6 damage), they leap away (movement, possibly incurring an opportunity attack), Hide (action), and prepare to attack from hiding again. If they’ve taken a serious hit (7 damage or more), they Dash (action, possibly incurring an opportunity attack) back home. If they haven’t taken any damage, they attack one more time.

On their third turn, assuming they still outnumber their enemies by at least two to one, they all try to grapple their targets. If the first grung of a pair succeeds on its grapple, the second one takes the Help action to grant it advantage on its roll to keep the opponent grappled should they try to escape. A successful grapple requires the target to make a DC 12 Constitution saving throw against being poisoned. The poisoned condition gives the target disadvantage on all attack rolls and ability checks; in addition, if you’re using the Grung Poison variant, the poisoned target can no longer move except to climb or make standing jumps.

On their fourth turn, those grungs that have successfully grappled their opponents haul them off, while those that haven’t keep trying until their opponents are subdued or their numbers are too badly reduced for them to keep fighting.

If a grung fails two grapple attempts in a row against a particular target, it gives up on this tactic and goes back to attacking with its dagger.

Grung wildlings have spellcasting ability, and this ability is nastier than it looks at first, because of how their spells can be combined. Specifically, spike growth plus plant growth is a killer combination. Plant growth instantaneously causes all normal plants within a 100-foot radius to grow so thick that movement is slowed by a factor of four. (This doesn’t inhibit the grungs’ movement, since they can jump over the growth rather than have to slog through it.) Spike growth, meanwhile, deals piercing damage to any creature moving into or through its area of effect. Because plant growth gives not only a grung wildling but also all its allies a comparative advantage over their foes, a wildling casts this spell on its first turn and follows up with spike growth on its second, casting it where it can catch at least four enemies in the area of effect. If the wildling’s enemies are too spread out for it to target four of them with spike growth, it uses its second turn to cast barkskin on itself instead. (It can’t sustain both of these spells at the same time.)

On its third turn and thereafter, the grung wildling supports its team, shooting into the melee with its shortbow. If at any time it needs to jump away, it does so with the help of the jump spell, which allows it to jump a distance of 75 feet (and remains in effect for a full minute, without concentration). It uses cure wounds only to support an elite warrior, if one is present.

Grung wildlings are red grungs, and a creature affected by their toxin is overcome by hunger and uses its action to eat any food it can get at.

A grung elite warrior has the same combat abilities as an ordinary grung, only better, plus the Mesmerizing Chirr action. This feature stuns non-grungs within earshot who fail their saving throws, so that they can’t take actions or reactions and automatically fail Strength and Dexterity saves, and attacks against them have advantage. If a PC spots the grungs before they launch their attack from hiding, the grung elite warrior uses this feature right away, to try to regain the advantage denied by their blown cover. Otherwise, it uses it on its second turn, and again as soon as it recharges.

Aside from this, the grung elite warrior fights as a normal grung, with a couple of exceptions.

First, the elite warrior can take a lot more hits than an ordinary grung can, so it doesn’t leap away when it takes one, unless that hit seriously wounds it (reduces it to 19 hp or fewer).

Second, in that instance, it calls a retreat and takes the Disengage action rather than the Dash action, fighting as a rearguard while its allies disperse; it only leaps away itself once all its allies are safely gone.

Third, grung elite warriors are orange grungs. Their Grung Poison causes the victim to be frightened of their allies. A close reading of the frightened condition is important here: "A frightened creature has disadvantage on ability checks and attack rolls while the source of its fear is within line of sight" (Player’s Handbook, appendix A, emphasis mine). This rule is easily distorted by imperfect memory into having disadvantage on attack rolls against whatever the frightened creature is frightened of; in fact, a PC who’s frightened of their own allies has disadvantage on all attack rolls—and ability checks—as long as any ally is visible. Thus, once a grung elite warrior grapples an enemy, if that enemy fails their save against being poisoned, they have disadvantage on attempts to break the grapple as long as one of their own allies is still in view. And if the grungs are carrying the whole party off together…

Fourth, key locations within the grungs’ territory may be heavily guarded by elite warriors. These grungs don’t mess around with the kidnapping shtick. They stand at a distance and pincushion intruders with poisoned arrows.

KOBOLDS (V)

Volo’s includes stat blocks for three new varieties of kobold: the kobold dragonshield, the kobold scale sorcerer, and the kobold inventor.

The kobold dragonshield is simply an exceptionally strong kobold with a melee Multiattack and selective elemental damage resistance. These don’t affect its tactics, nor does its Heart of the Dragon feature, which allows it to shake off the frightened or paralyzed condition and do the same for allies around it. But its above-average Dexterity and Constitution, as well as its greater number of hit points, reduce its dependence on ranged combat and make it an effective skirmisher. Kobold dragonshields are bold nuisances, charging in to jab with their spears, then Dodging as they retreat. In kobold lairs, they use this maneuver to draw their pursuers into tight situations or traps, Multiattacking until they take a light wound (5