Cerebral Mimic

False Appearance (Object Form). While motionless, the Cerebral Mimic is indistinguishable from an ordinary object (books, scrolls, artifacts, etc.).

Psionic Feedback. When attacked while draining Intelligence, the Cerebral Mimic releases a Psychic Shockwave. All creatures within 10 ft. must succeed on a DC 15 Intelligence saving throw or take 3d8 psychic damage and have disadvantage on Intelligence-based checks and saving throws for 1 hour.

Absorb Knowledge. For each Intelligence point drained, the mimic temporarily gains proficiency in one of the target's Intelligence-based skills (e.g., Arcana, History) and can cast any Intelligence-based spells the target knows, using its new Intelligence modifier.

Multiattack. The Cerebral Mimic makes two Intellect Drain attacks.

Intellect Drain. Melee Weapon Attack: +6 to hit, reach 5 ft., 1 target. On hit, the target takes 2d6 psychic damage and loses 1d4 Intelligence points. The reduction lasts until the target finishes a long rest or is healed by a spell like Greater Restoration. If Intelligence is reduced to 0, the target falls unconscious.

Psychic Blast (Recharge 5-6). The mimic emits a psionic burst. All creatures within 30 ft. must make a DC 15 Intelligence saving throw, taking 4d8 psychic damage on a failed save, or half as much on a successful one.

Can only be used 1/Day.

Memory Implant. After draining a creature’s Intelligence to 0, the mimic implants a psychic parasite. The target regains Intelligence slowly but becomes a thrall under the mimic’s control unless a spell like Remove Curse or Greater Restoration is used.