Buzzwole (5e Creature)
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Large aberration, neutral
Beast Boost. When Buzzwole reduces a hostile creature to 0 hit points, the attack bonus for its melee weapon attacks increases by 2, and the damage for those attacks increases by 2d8. This bonus is cumulative, but resets when Buzzwole takes a long rest.
Multiattack. Buzzwole makes three attacks: two with its fists and one with its leech life.
Fist. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 9 (1d8 + 5) bludgeoning damage.
Leech Life. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 9 (1d8 + 5) bludgeoning damage plus 14 (4d6) necrotic damage, and Buzzwole regains a number of hit points equal to the necrotic damage take.
Codenamed UB-Absorption, this Ultra Beast resembles a humanoid, muscular mosquito. It attacks with its powerful fists, and uses its proboscis to drain blood from enemies it fights and restore life to itself. Its strength increases as it defeats its foes.