"Three hooded figures, knocking on the door. Delivering news that you will abhorr. Death to man! Death to the weakest! Death brought upon by the greatest illness" Instinct: To bring news of death

• Knock on someone's door

Some are wont to lump these little, rat-like dragon-men in with goblins and orcs, bugbears and hobgoblins. They are smarter and wiser than their kin, however. The kobolds are beholden slaves to dragons and were, in ancient times, their lorekeepers and sorcerer-servants. Their clans, with names like Ironscale and Whitewing, form around a dragon master and live to serve and do its bidding. Spotting a kobold means more are near—and if more are near then a mighty dragon cannot be far, either. Instinct: To serve dragons

• Lay a trap
• Call on dragons or draconic allies
• Retreat and regroup

[They] carefully entered the cavern, and were instantly assaulted by the scent of blood. The cavern floor [...] was deep with the creatures’ blood-red guano. (Tim Richardson, “Ecology of the Stirge”) Instinct: To suck blood

• Attach to an enemy
• Redirect an attack to its prey.
• Drink blood through its proboscis.
• See in the dark

The Medusa of Demon Castle Dracula spawns flying serpent-haired heads that sweep through her lair to spy out and drive off intruders. Heroes who pass this hideous gauntlet may come face to face with their foul brood-mother. To these, the Medusa may grant the gift of eternal slumber, as a statue among the ruins of this age. Instinct: To make heroes immortal

• Overwhelm them or knock them down with a gale of medusa heads
• Turn a worthy enemy to stone with a look
• Draw someone's gaze
• Summon winds

The acid deals 1d4 of dmg at the beginning of each round, during 1d6 rounds Instinct: To eat

• Goes inside the clothes or armor
• They inject acid when they bite.

Each individual shadow is actually a swarm of tiny, dust-sized demons. No one is quite sure where they come from, or how to kill them, but it is known that children of every species on every plane of existence know to fear the darkness . . . Instinct: To spread

• Devour flesh
• Impersonate voices
• Absorb knowledge from those it kills

The recently killed corpses of your fellow comrades have been brought back as the undead and will stop at nothing to kill you! Instinct: To end life

• Attack the living

Created for the ancient gods of chaos, Shoggoths are shapeless protoplasmatic creatures, made of gelatinous black mucus in constant mutation. Originally created as slaves and servants, shoggoths are able to mold your bodies, assuming temporally anyform, including organs of high complexity (like eyes, ears, vocal cords, legs, arms, wings and tails). In ancient times, the shoggoths assume humanoid forms to infiltrate in cities and villages, with the purpose of bring worshippers to your masters, and consecrate the power of chaos, from bizarre ritualistic orgies. Maybe this time, can this old custom still exist, drowning men into chaos? Instinct: Obbey to its master

• Disguise as a Humanoid
• Metamorphosis
• convince others to serve the Chaos

Absolutely devoted to eventually escaping the Dungeon, the Hermit Dragon has spent ages poring over secrets, investigating the workings of the Dungeon, and scribing spells the likes of which the world has rarely seen. I hope you've got some juicy information to offer it if you interrupt it, though. Behind its robe-draped form is a barely-contained engine of primordial power, waiting to unleash itself on those foolish enough to interrupt its singleminded research. Instinct: To continue its lonely research

• When left alone, assume an innocuous human form
• When bothered, wither interlopers with merely a glare
• When enraged, breathe elemental force
• When appeased with new knowledge, reveal a secret hidden for ages
• When confronted, reveal yourself in all your terrible glory

When they heard of a chance to show off in front of the emperor, of course they signed up. Brought their Owlbear mascot with them, as well. Instinct: to show how much better they are

• Parry and riposte
• feint and disarm