Mimic

Armor Class 12 (natural armor)
Hit Points 58 
XP LVL: 2 (450xp)
Speed 15 ft.
STR 17 (+3)
DEX 12 (+1)
CON 15 (+2)
INT 5 (-3)
WIS 13 (+1)
CHA 8 (-1)
Skills Stealth +3
Damage Immunities acid
Condition Immunities prone
Senses darkvision 60 ft., passive Perception 11
Languages understands Common but can't speak
Shapechanger. The mimic can use its action to polymorph into an object 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 object.
Grappler. The mimic has advantage on attack rolls against any creature grappled by it.
Actions
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 7 (1d8 + 3) piercing damage.
Engulf. The mimic moves up to its speed and can enter a Large or smaller creature's space. That creature must make a DC 13 Strength saving throw. On a failure, the mimic enters the creature's space, and the creature is grappled. The grappled creature takes 10(2d6 + 3) bludgeoning damage and 10(3d6) acid damage at the start of the mimic's turn. Until the grapple ends, the target is restrained, and the mimic can't move. The mimic can have only one creature grappled at a time.