Chitter

Maddening Chatter. The chitter babbles incoherently while it can see any creature and isn't incapacitated. Each creature that starts its turn within 20 feet of the chitter and can hear the babbling must succeed on a DC 10 Wisdom saving throw. On a failure, the creature can't take reactions until the start of its next turn and rolls a d8 to determine what it does during its turn. On a 1 to 4, the creature does nothing. On a 5 or 6, the creature takes no action or bonus action and uses all its movement to move in a randomly determined direction. On a 7 or 8, the creature makes a melee attack against a randomly determined creature within its reach or does nothing if it can't make such an attack.

Multiattack. The chitter makes one bite attack and, if it can, uses its insane babble.

Bite. Melee Weapon Attack: +2 to hit, reach 5 ft., one creature. Hit: 7 (2d6) piercing damage.

Insane Babble (Recharge 4–6). The chitter shrieks ancient words of confusion and insanity at all creatures within 15 feet of it. Each of these creatures must succeed on a DC 13 wisdom saving throw or be charmed until the end of the chitter's next turn. If the save fails by 5 or more, the creature is paralyzed while charmed in this way.