Multiattack

The mire fiend makes one Mandibles attack, one Spear attack, and one Stinger attack.

Mandibles

_Melee Weapon Attack:_ +6 to hit, reach 5 ft., one creature. _Hit:_ 12 (2d8+3) slashing damage.

Spear

Melee Weapon or Ranged Attack: +5 to hit, reach 5 ft. or range 20/60 ft., one target. _Hit:_ 5 (1d6+2) piercing damage, or 6 (1d8+2) piercing damage if used with two hands to make a melee attack.

Stinger

_Melee Weapon Attack:_ +6 to hit, reach 10 ft., one creature. _Hit:_ 5 (1d4+3) piercing damage plus 10 (3d6) poison damage, and the target must succeed on a DC 14 CON save or be poisoned.

Stunning Snap (Recharge 5-6)

If the mire fiend has no creature grappled, it snaps its mandibles together with great force, creating a miniature sonic boom in a 30-foot cone.<br>Each creature in that area must make a DC 14 CON save. On a failure, a creature takes 21 (6d6) thunder damage and is stunned until the end of its next turn. On a success, a creature takes half the damage and isn't stunned.