Some mimics prefer a symbiotic relationship to a strictly predatory one. A case in point is this monstrosity that prefers the shape of an ornate vase, and not the sort for decoration alone. Oh no, this mimic will plant and tend to greenery all on its own if it has too. Not only does it find the companionship soothing, but it can also then use the plant and others as an ally of sorts in combat. That and, many adventurers discount it as a mimic out of hand because of the living thing within. More fertilizer for its leafy friends.

Jardinière Mimic

Medium monstrosity (shapechanger), neutral

Armor Class 13(natural armor)

Hit Points 65 (10d8 + 20)

Speed 15 ft

Str 18 Dex 11 Con 14 Int 5 Wis 16 Cha 8

Skills Nature +1, Stealth +4

Damage Resistances poison

Damage Immunities acid

Condition Immunities prone

Sensesdarkvision 60 ft, passive Perception 11

Languages -

Challenge 3 (700 XP)

Shapechanger.

The mimic can use its action to polymorph into an artistic planter 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 14). 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 an artistic planter.

Grappler.

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

Grass Roots.

The mimic takes control of a living, non-sentient plant of Small size within 5ft and uses it as an animated tool and weapon. The plant becomes a defacto awakened shrub for the next minute or until the mimic dies. The plant does not attack or move on its own. The mimic can use a bonus action to have the shrub move or attack. The mimic cannot control more than one plant at a time.

Actions

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.

Nourish (Object Form Only).

The mimic restores 3(1d6) hit points to a plant it can see within 30ft and provides the water and nutrients it needs for 1 day.

Spit Poison.

While Grass Roots is active, the mimic may use its action to spit poison manufactured from the linked plant at a target it can see within 30ft. If the target is a creature, it must succeed on a DC 12 Constitution save or be Poisoned for the next minute. An affected creature can repeat this save at the end of each of its turn with the effect ending on success.