Shapechanger. The mimic can use its action to polymorph into a beer keg or wine 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 Large or smaller creature adhered to the mimic is also grappled by it (escape DC 12). 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 keg.

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

Pseudopod. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) bludgeoning damage. If the mimic is in object form, the target is subjected to its Adhesive trait.

Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) piercing damage plus 3 (1d6) acid damage and the target must make a DC 12 Constitution saving throw.  On a failure, the target is inebriated.  An inebriated creature is poisoned for 1 minute.  While poisoned this way, the target suffers 1 random effect.  Roll a d10 to determine the effect from the options below:

If an inebriated creature is subject to another inebriation effect, it rolls on the table again (rerolling any duplicates), suffering an additional effect.

At the end of each of its turns, an inebriated creature can repeat the saving throw, ending one inebriation effect on a success.  The effect that ends is the one the target has suffered the longest.  When the target is free of all inebriation effects, it is also free of being poisoned.  A spell or effect that cures the poisoned condition also cures all inebriation effects.