Steam Mephit

Attack rolls against the monster are made with Disadvantage unless the monster has the Incapacitated condition.

The monster explodes .
Dexterity Saving Throw: DC , each in a -foot Emanation originating from the monster.
Failure: damage.
Success: Half damage.

. .

Constitution Saving Throw: DC , each creature in a -foot Cone.
Failure: damage, and the target's Speed decreases by 10 feet until the end of the monster next turn..
Success: Half damage.
Failure or Success: Being underwater doesn't grant Resistance to this Fire damage.