Corrupted Pegasus

Awakened Potential. The creature’s weapon attacks are magical. When it hits with any weapon, the weapon deals an extra 4d8 necrotic damage.

Bound to Serve. When the creature receives this template, it is bound to a specific individual. The creature must obey that individual’s every command, even if it leads to the creature’s death.

Built for War. The creature’s weapon attacks score a critical hit on a roll of 18–20.

Magic Resistance. The creature has advantage on saving throws against spells and other magical effects.

The Cost. The creature cannot deal radiant damage or cause itself or other creatures to regain hit points. Any such abilities it uses have no effect.

Truthseeker. The creature knows when it hears a lie.

Hooves. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) bludgeoning damage and 18 (4d8) necrotic damage.

Perfect Strike. The creature can make a weapon attack against AC 10. If it hits, the target takes necrotic damage equal to half its hit point maximum. The corrupted celestial can use this ability three times, regaining all expended uses when it finishes a short or long rest.