Baernaloth

If the baernaloth fails a saving throw, it can choose to succeed instead.

The baernaloth has advantage on saving throws against spells and other magical effects.

The baernaloth makes one Anguishing Bite attack and one Claw attack. It can also use Teleport.

Melee Weapon Attack +10 to hit, reach 5 ft., one target. 9 (1d10 + 4) Piercing damage plus 10 (3d6) Psychic damage. If the target is a creature, it can't regain hit points until the start of the baernaloth's next turn.

Melee Weapon Attack +10 to hit, reach 10 ft., one target. 11 (2d6 + 4) Slashing damage plus 17 (5d6) Necrotic damage.

The baernaloth exhales gray vapors that coalesce at a point it can see within 120 feet of itself. The vapors fill a 20-foot-radius sphere centered on that point, then vanish. Each non-yugoloth creature in that area must make a DC 19 Wisdom saving throw. On a failed save, the creature takes 35 (10d6) Psychic damage and has the Charmed condition until the end of its next turn. A creature Charmed in this way treats its allies as foes, and the colors of its body and equipment become shades of gray. On a successful save, the creature takes half as much damage only.

The baernaloth has a 50 percent chance of summoning its choice of 1d4 mezzoloths, 1 arcanaloth, or 1 baernaloth (the mezzoloth and arcanaloth appear in the Monster Manual). A summoned yugoloth appears in an unoccupied space within 60 feet of the baernaloth, acts as an ally of the baernaloth, and can't summon other yugoloths. It remains for 1 minute, until it or the baernaloth dies, or until the baernaloth dismisses it as an action.

The baernaloth teleports, along with any equipment it is wearing or carrying, up to 120 feet to an unoccupied space it can see.

When a creature that the baernaloth can see within 60 feet of itself hits with an attack roll or succeeds on a saving throw, the baernaloth forces the creature to reroll the d20 and use the new result.

When the baernaloth is damaged by another creature, that creature must make a DC 19 Constitution saving throw, taking 14 (4d6) Necrotic damage on a failed save, or half as much damage on a successful one.