Stakataka (5e Creature)
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Huge aberration, neutral
Saving Throws INT +3, WIS +5, CHA +3
Beast Boost. When Stakataka reduces a hostile creature to 0 hit points, its armor class and all of its saving throws increase by 1. This bonus is cumulative, but resets when Stakataka takes a long rest.
Reflective Carapace. Any time Stakataka is targeted by a magic missile spell, a line spell, or a spell that requires a ranged attack roll, roll a d6. On a 1 to 5, Stakataka is unaffected. On a 6, Stakataka is unaffected, and the effect is reflected back at the caster as though it originated from Stakataka, turning the caster into the target.
Slam. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 21 (5d6 + 4) bludgeoning damage.
Body Press. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 39 (10d6 + 4) bludgeoning damage. Miss: Stakataka falls prone.
At first glance, and even after light inspection, Stakataka appears to be a heap of stone and metal, but when threatened, it assembles into an Ultra Beast that uses its body to crush opponents and shields itself from most attacks