The ballistae can't perceive (and thus they ignore) creatures that keep to the easternmost 60-foot section of the hallway. Once they detect intruders, however, the ballistae amble forward on hinged legs to close the distance. If a ballista has nothing to attack on its turn, it returns to its starting position. Instinct: Protect the area

• Shoot a bolt of fire

Privileged drow males who lack the strength and fighting prowess to train as warriors have no recourse but to pursue the study of magic. For them, it is a matter of survival. Female drow with a natural affinity for the arcane arts may also become drow mages, although they are much less common. Instinct: Seek Political Gain

• Summon an Imp/Quasit or Shadow Demon
• Summon magical darkness
• Cast Magic Missile (2d4 damage)
• Block an Attack with a Shield Spell
• Cast Fireball (2d6 ignores armor)
• Cast Cloudkill
• Levitate!

The bulk of the yugoloth population is made up of mezzoloths, which are human-sized insect creatures covered in dense chitinous plates. Mezzoloths serve as foot soldiers in yugoloth armies, their wide-set eyes glowing red as the mezzoloths bear down on their foes. Violence and reward are the fundamental drives of a mezzoloth, and powerful beings that promise one or the other can easily attract them into service. Although it has lethal claws on its four arms, a mezzoloth typically wields a trident in two of them. If surrounded by enemies, a mezzoloth exhales toxic fumes that can choke and kill whole groups of creatures. Instinct: Violence and reward

• Teleport to anywhere it can see
• If surrounded exhales toxic fumes that can choke and kill (extra d6 damage when damaged)
• Use magic to darken the area
• End a magical effect

A revenant forms from the soul of a mortal who met a cruel and undeserving fate. It claws its way back into the world to seek revenge against the one who wronged it. The revenant reclaims its mortal body and superficially resembles a zombie. However, instead of lifeless eyes, a revenant’s eyes burn with resolve and flare in the presence of its adversary. If the revenant’s original body was destroyed or is otherwise unavailable, the spirit of the revenant enters another humanoid corpse. Regardless of the body the revenant uses as a vessel, its adversary always recognizes the revenant for what it truly is. Instinct: Exact vengence before it's year is up

• track those it seeks revenge against
• Paralyze it's sworn enemy with a glare
• regenerate wounds not caused by fire

A nothic is a monstrous creature with terrible talons and a single great eye. When driven to violence, it uses its horrific gaze to rot the flesh from its enemies’ bones. Rather than gaining the godlike supremacy they crave, some wizards who devote their lives to unearthing arcane secrets are reduced to creeping, tormented monsters by a dark curse left behind by Vecna, a powerful lich who, in some worlds, has transcended his undead existence to become a god of secrets. Nothics retain no awareness of their former selves, skulking amid the shadows and haunting places rich in magical knowledge, drawn by memories and impulses they can’t quite understand. Instinct: Reverse its condition

• Rot living flesh with its gaze
• Gaze at someone and learn one fact or secret about them

Of all the terrors created by foul sorcery, gibbering mouthers are among the most wicked and depraved. This creature is the composite eyes, mouths, and liquefied matter of its former victims. Tormented by the destruction of their bodies and absorption into the mouther, those victims gibber incoherently and are forced to consume everything in reach. Instinct: Consume Everything in Reach

• Warp the ground around it to dough
• Drive listeners temporarily insane
• Blind somone with a gob of spit hat explodes in light

The draugr or draug is an undead creature from the Scandinavian saga literature and folktales. Commentators extend the term draugr to the undead in medieval literature, even if it is never explicitly referred to as such in the text, and designated them rather as a haugbúi ("barrow-dweller") or an aptrganga, literally "again-walker" (Icelandic: afturganga).Draugar live in their graves or royal palaces, often guarding treasure buried with them in their burial mound. They are revenants, or animated corpses with a corporeal body, rather than ghosts which possess intangible spiritual bodies.The draugr was referred to as "barrow-wight" in the 1869 translation of Grettis saga, long before J. R. R. Tolkien employed this term in his novels, though "barrow-wight" is actually a rendering of haugbúinn (literally the ‘howe-dweller’), otherwise translated as "barrow-dweller" Instinct: Slays intruders

• Guards

A jiāngshī, also known as a Chinese hopping vampire, is a type of reanimated corpse in Chinese legends and folklore. It is typically depicted as a stiff corpse dressed in official imperial garments and it moves around by hopping with its arms outstretched. It kills living creatures to absorb their "life force", usually at night, while during the day, it rests in a coffin or hides in dark places such as caves. Generally, a jiangshi's appearance can range from unremarkable (as in the case of a recently deceased person) to horrifying (rotting flesh, rigor mortis, as with corpses that have been in a state of decay over a period). It is believed that the jiangshi are so stiff that they cannot bend their limbs or body, so they have to move around by hopping while keeping their arms stretched out for mobility. Folklore and burial practices dealing with revenants can also be traced back to Norse mythology with draugr or draug(s) that closely resemble stories of jiangshis. Instinct: Drains Life

• Hops

The barkeep asked why we carried weapons into his bar. I said ‘Mimics.’ The party laughed. The barkeep laughed. The table laughed. We killed the table. Good times. Instinct: To Eat

• Adheres to Someone

New tasks were given to the fungus ones as they grow older. Sprouts work as hands for their respective elders, assisting with daily chores, and responsible for releasing distress spores if hostiles approached. Normal adults do most of the basic work. Elders were responsible for supervising the work of other myconids.By the time they are 20 a single myconid in a community could undergo a great change in size, becoming much larger and transforming into sovereigns or lords through a special regiment process if a community leader is needed. Every myconid community has its population under careful control. All older members are its leaders who administrate and advise the myconid king, the only entity above them. Leaders and kings preferred to lead from the back, only joining into combat if they believed their community to be in actual danger. To be a sovereign was the most dreaded position within the myconid community, seen as practically a punishment. Because the myconid sovereign was tasked with being objective to the circles and administrating their duties, it could not become part of a circle, and could never again meld with those of its tribe. The duties of the king include the creation of spore zombie servants so that the myconids can remain pacifistic, the coordination of work schedules and the production of useful fungal magical potions. Spore zombies resemble normal zombies but are nonmagical constructs controlled by the myconid leader to defend the colony and can not be turned by a cleric. Instinct: Protect Colony

• Rule myconids
• Summon spore zombies
• Create spore zombies