Raised by a vengeful noble, the cask mimic was first trained to protect the man's most precious vintages and to keep his favorite foods fresh far longer than they should. Then, one day the noble had it devour an unfaithful spouse and hide the body from the authorities. Over time, only the bones remained within the monstrosity's mass. The fickle blueblood decided to scold and beat their fine pet one day and in response, the mimic spat the bones at them. To both their surprise, the skeleton protected the mimic, strangled the noble, and then fell inert. In the end, everyone assumed the noble was killed by a vengeful spirit and the mimic continued on, undetected.

Cask Mimic

Medium monstrosity (shapechanger), neutral

Armor Class 15 (natural armor)

Hit Points 75 (10d8 + 30)

Speed 15 ft

Str 16 Dex 12 Con 16 Int 5 Wis 13 Cha 15

Skills Stealth +5

Damage Resistances necrotic

Damage Immunities acid, poison

Condition Immunities prone

Sensesdarkvision 60 ft, passive Perception 11

Languages understands All but cannot speak

Challenge 4 (1,100 XP)

Shapechanger.

The mimic can use its action to polymorph into a barrel, cask, or back into its true, amorphous form. Its statistics are the same in each form. Any equipment it is wearing or carrying isn't transformed. It reverts to its true form if it dies.

Adhesive (Object Form Only).

The mimic adheres to anything that touches it. A Huge or smaller creature adhered to the mimic is also grappled by it (escape DC 13). Ability checks made to escape this grapple have disadvantage.

False Appearance (Object Form Only).

While the mimic remains motionless, it is indistinguishable from an ordinary cask or barrel.

Fresh (Object Form Only).

Any item stored within the mimic while it is in object form remains fresh and spoilage free for as long as the mimic remains in that state.

Grappler.

The mimic has advantage on attack rolls against any creature grappled by it.

Actions

Multiattack.

The mimic makes two pseudopod attacks.

Pseudopod.

Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 7 (1d8 + 3) bludgeoning damage. If the mimic is in object form, the target is subjected to its Adhesive trait.

Bite.

Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 7 (1d8 + 3) piercing damage plus 4 (1d8) acid damage.

Barrel Roll (Object Form Only)(Recharge-5-6).

The mimic travels in a 30ft line that is 5ft wide. All creatures in the area of effect must succeed on a DC 13 Dexterity save or take 10 (3d6) bludgeoning damage and be knocked If a creature fails this save by 5 or more it is subject to the mimic's adhesive trait and travels with the mimic. This movement does not provoke opportunity attacks.

Bonus Actions

Mimic Pellet.

After consuming a medium creature, the mimic may retain its skeleton for up to one year. As a bonus action, the mimic may discharge that skeleton, which animates and aids the mimic for 1d4 rounds before falling to pieces. This skeleton counts as a construct instead of an undead.