Boyu-Kasha

Innate Spellcasting. Boyu-Kasha has the following innate casting abilities. Its spellcasting ability is Charisma (spell save DC 25, +18 to hit with spell attacks). Boyu-Kasha can innately cast the following spells, requiring no material components:
At will: Eldritch Blast (4 bolts), Misty Step, Vampiric Touch

3/day: Blight, Destructive Wave (necrotic), Elemental Bane, Cure Wounds (self, 8th level)

2/day: Feeble Mind, Force Cage, Freezing Sphere, Harm

1/day: Psychic Scream, Weird, Illusory Dragon (cold/necrotic)

Legendary Resistance. Boyu-Kasha has 4 legendary resistances. When he fails a saving throw he can choose to succeed instead.

Magic Resistance. Boyu-Kasha has advantage on saving throws against spells and magical effects

Multiattack. Boyu-Kasha can make three Rapier attacks per turn in his humanoid form. Alternatively, he can make an attack as a Bonus Action after casting any spell. While in beast form Boyu-Kasha makes four claw attacks per turn and can cast one of his at will spells as a Bonus Action. These attacks are all magical.

Rapier Frost Brand. Melee Weapon Attack: (Humanoid Form only)+18 to hit, reach 5 ft., 1 target. Hit: 20 (2d8 + 11) piercing damage and 10 (3d6) cold damage and 8 necrotic damage.

Claws. Melee Weapon Attack: (Beast form only)+20 to hit, range 15 ft., 1 target. Hit: 34 (4d12 + 8) slashing damage and 26 (4d8 + 8) necrotic damage.

Become Beast. When Boyu-Kasha drops to 483 (half) hp he immediately uses his reaction to transform into a bestial form. In this form his Charisma and Strength scores switch. He loses the ability to cast any spells other than his At Will powers. Boyu-Kasha's AC increases to 25 and his spell save DC drops to 20 when he assumes Beast form. If he heals to above 483 hp he returns to his humanoid form.

Boyu-Kasha has 5 legendary actions. Boyu-Kasha can spend any number of legendary actions at the end of another creatures turn to perform one of the following actions. He can only use one option at a time and can only use any one action once per round.

Regeneration (Costs 1 Actions). Boyu-Kasha immediately regains 4d10 health.

Summon Soul (Costs 2 Actions). Boyu-Kasha summons 1 specter and 1d8 souls to torment a target. The specter attacks only a single creature. The souls summoned take on the form of the targets closest loved ones that have passed on. These souls cause the target to have disadvantage on all attacks and saving throws until the specter is slain, Boyu-Kasha drops to 0, or this ability is used again.

Counter spell (Costs 3 Actions). Boyu-Kasha can cast the spell Counter spell (this takes place when a spell is cast not at the end of another creatures turn.

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