MM, page 215. Also found in PotA; SKT; TftYP; EGW; IDRotF; CM; KftGV. Available in the SRD.
Ice Mephit CR: 1/2
Small elemental, any non-lawful
Armor Class: 11 (natural armor)
Hit Points: 21 (6d6) 6d6
Speed:
30 ft
, fly: 30 ft
Skills: Perception +2, Stealth +3
Proficiency Bonus +2
Damage Vulnerabilities: bludgeoning, fire
Damage Immunities: cold, poison
Condition Immunities: poisoned
Senses: darkvision 60 ft., passive Perception 12
Languages: Aquan, Auran
Challenge Rating: 1/2
1/day: The mephit can innately cast fog cloud, requiring no material components. Its innate spellcasting ability is Charisma.
Death Burst. When the mephit dies, it explodes in a burst of jagged ice. Each creature within 5 feet of it must make a DC 10 Dexterity saving throw, taking 4 (1d8) 1d8 slashing damage on a failed save, or half as much damage on a successful one.
False Appearance. While the mephit remains motionless, it is indistinguishable from an ordinary shard of ice.
Actions
Claws. Melee Weapon Attack: +3 to hit, reach 5 ft., one creature. Hit: 3 (1d4 + 1) 1d4+1 slashing damage plus 2 (1d4) 1d4 cold damage.
Frost Breath (Recharge 6). The mephit exhales a 15-foot cone of cold air. Each creature in that area must succeed on a DC 10 Dexterity saving throw, taking 5 (2d4) 2d4 cold damage on a failed save, or half as much damage on a successful one.
Mephits are capricious, imp-like creatures native to the elemental planes. They come in six varieties, each one representing the mixture of two elements.
Ageless tricksters, mephits gather in large numbers on the Elemental Planes and in the Elemental Chaos. They also find their way to the Material Plane, where they prefer to dwell in places where their base elements are abundant. For example, a magma mephit is composed of earth and fire, and it favors volcanic lairs, while an ice mephit, which is composed of air and water, favors frigid locales.
Elemental Nature. A mephit doesn't require food, drink, or sleep.
Ice Mephit
Comprising frigid air and water, ice mephits are aloof and cold, surpassing all other mephits in pitiless cruelty
Variant: Summon Mephits (1/Day)
The mephit has a 25 percent chance of summoning 1d4 mephits of its kind. A summoned mephit appears in an unoccupied space within 60 feet of its summoner, acts as an ally of its summoner, and can't summon other mephits. It remains for 1 minute, until it or its summoner dies, or until its summoner dismisses it as an action.
Suggested Environments
Environment: Arctic