mimic

A person who practices mimicry.

A comic who does impressions.

An entity that mimics another entity, such as a disease that resembles another disease in its signs and symptoms; see the great imitator.

A fictional monster able to disguise itself as an inanimate object, commonly a treasure chest, often with the intent of luring adventurers into a trap.

An imitation.

A mime.

copying something else closely in look, sound or action, as some insects copy the look of leaves

Imitative; characterized by resemblance to other forms; applied to crystals which by twinning resemble simple forms of a higher grade of symmetry.

made or done to look like the real thing but not real, such as a battle fought only for practice

To imitate, especially in order to ridicule.

To take on the appearance of another, for protection or camouflage.