Much like a curious cat becoming fascinated with sunbeams reflected on the wall, the gaslight mimic is so enamored with light that it sought a form that could produce it. While the basic shape was easy enough to assume, the actual illumination proved difficult. The mimic worked the angles of its false glass, studied the way fires worked and then had the good luck to devour an illusionist. Not long after, it found a way to produce a false light, much to its delight. Over time, the gaslight mimic and its ilk figured out how to produce slightly more complex illusions or even blind its prey when necessary.

Gaslight Mimic

Small monstrosity (shapechanger), neutral

Armor Class 13 (natural armor)

Hit Points 66 (12d6 + 24))

Speed 15ft

Str 15 Dex 15 Con 15 Int 5 Wis 13 Cha 14

Skills Stealth +6

Damage Resistances radiant

Damage Immunities acid

Condition Immunitiesprone

Sensesdarkvision 60 ft., passive Perception 11

Languages -

Challenge 3 (700 XP)

Shapechanger.

The gaslight mimic can use its action to polymorph into a lantern 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.

While the mimic remains motionless, it is indistinguishable from an ordinary lamp.

Grappler.

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

Illumination.

The gaslight mimic sheds bright light in a 30-foot radius and dim light in an additional 60 ft. It can activate or deactivate this ability as a bonus action

Innate Spellcasting (at will).

The gaslight mimic can innately cast Minor Illusion (spell save DC 12), requiring no material components. Its innate spellcasting ability is Charisma.

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.

Flash.

The gaslight mimic emits an ear-searing flash of light with a radius of 30 ft. All creatures within the area of effect must succeed on a DC 12 Dexterity save or be Blinded for the next minute. An affected creature may repeat this save at the end of each of its turns, the effect ending on success.