Kartana (5e Creature)
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Tiny aberration, neutral
Beast Boost. When Kartana reduces a hostile creature to 0 hit points, the attack bonus for its melee weapons attacks increases by 5, and it gains an additional use of its Sharpened Blade. This bonus is cumulative, but resets when Kartana takes a long rest.
Magic Weapons. Kartana's weapon attacks are magical.
Sharpened Blade (3/day). When Kartana hits with an attack, it can choose to score a critical hit instead.
Sacred Sword. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 27 (6d6 + 6) slashing damage.
Kartana appears at first to be a delicate origami sculpture of a blade, but its body is as tough as steel and its blades are sharp enough to cut through the air itself. Despite being the smallest of the ultra beasts, it is just as powerful as all the rest of them.