Multiattack

The flutterflesh makes three Bone Spur or Tormenting Gaze attacks. If two Tormenting Gaze attacks hit one creature, the target must succeed on a DC 16 Wisdom saving throw or be paralyzed for 1 minute. A paralyzed creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Bone Spur

Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 17 (2d12 + 4) piercing damage plus 9 (2d8) necrotic damage, and the flutterflesh impales the target on one of its bone spurs, grappling the target (escape DC 16). The flutterflesh can have no more than two creatures impaled at a time.

Tormenting Gaze

Ranged Spell Attack: +7 to hit, range 120 ft., one creature. Hit: 21 (4d8 + 3) psychic damage.

Creeping Death (Recharge 5-6)

The flutterflesh emits a wave of necromantic energy, hastening the journey toward death. Each creature within 20 feet of the flutterflesh must make a DC 16 Constitution saving throw, taking 45 (10d8) necrotic damage on a failed save, or half as much damage on a successful one. A creature below half its hp maximum has disadvantage on this saving throw.