Belgoi

Darkvision. 60 feet.

Mental Defenses. The belgoi is immune to any effect that would sense its emotions or read its thoughts, including divination spells. Even wish spells and spells or effects of similar power cannot affect the belgoi's mind or gain information about it.

Multiattack. The belgoi makes two claw attacks.

Claws. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 7 (1d4 +4) slashing damage plus 4 (1d6 +1) psychic damage, and the creature's max hit points are reduced by an amount equal to the psychic damage taken for 1 hour.

Mindblast (Recharge 5-6). The belgoi magically emits psychic energy in a 30-foot cone. Each creature in that area must succeed on a DC 13 Intelligence saving throw or take 10 (2d8 +1) psychic damage and be stunned for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Psychic Bell. The belgoi rings its bell, targeting one creature within 120 feet of it. The target must succeed on a DC 13 Wisdom saving throw or be magically charmed while the belgoi rings its bell. The belgoi must use a bonus action on its subsequent turns to continue ringing its bell. The ringing stops if the belgoi is incapacitated or disarmed of its bell.

While charmed by the belgoi, a target is incapacitated and deafened; it can only hear the belgoi's bell. If the charmed target is more than 5 feet away from the belgoi, the target must move on its turn toward the belgoi by the most direct route, trying to get within 5 feet. It doesn't avoid opportunity attacks, but before moving into damaging terrain, such as lava or a pit, and whenever it takes damage from a source other than the belgoi, the target can repeat the saving throw. A charmed target can also repeat the saving throw at the end of each of its turns. If the saving throw is successful, the effect ends for it.

If a target succeeds on its initial saving throw, every creature within 60 feet of the belgoi can hear its bell and the belgoi loses this ability for the next 24 hours.