Fire Mephit

(from Planescape: Monstrous Compendium Appendix I - 1994):

The most mischievous of all mephits, these fiends play terrible pranks on other mephits, such as pushing magma mephits into water and watching them harden.

Fire mephits are small, wiry humanoids with bright red skin and bat-wings. Some fire mephits affect a mustache, goatee, and tiny horns on their forehead, but these are always faked.

Combat: Touching a fire mephit causes 1 hp heat damage. Its two clawed hands rake for 1d3 damage each plus 1 hp heat damage per hit.

Fire mephits can use their breath weapon three times a day. In one form it is a flame jet 15’ long and 1’ wide that automatically hits one chosen target (1d8+1 damage; save vs. breath weapon for half damage). The second form, a fan of flame, covers a 120 arc in front of the mephit to a distance of five feet. Any creature in the arc suffers 4 hp damage (no save).

Fire mephits can also cast magic missile (two missiles) and heat metal spells once each per day. Once per hour a fire mephit can attempt to gate in another mephit, either fire, magma, smoke or steam.

Ecology: Fire mephits sometimes prove useful heating forges, warming bedclothes, or lighting cigars.

(From 3.5e Monster Manual I - 2003):

This winged creature looks like a miniature devil, wreathed in flame and cackling with mischief. 

Fire mephits come from the Elemental Plane of Fire. A fire mephit is about 4 feet tall and weighs about 1 pound. 

Fire mephits speak Common and Ignan. 

Combat:

 Breath Weapon (Su): 15-foot cone, damage 1d8 fire, Reflex half DC 12. The save DC is Constitution-based and includes a +1 racial adjustment. 

Spell-Like Abilities: 1/hour—scorching ray (DC 14) as the spell cast by a 3rd-level sorcerer; 1/day—heat metal (DC 14). Caster level 6th. The save DC is Charisma-based. 

Fast Healing (Ex): A fire mephit heals only if it is touching a flame at least as large as a torch.