Black Oak (5e Creature)
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Large aberration (black arms), lawful evil
Martial Advantage. Once per turn, the black oak can deal an extra 7 (2d6) damage to a creature it hits with a weapon attack if that creature is within 5 feet of an ally of the black oak that isn't incapacitated.
Siege Monster. The black oak deals double damage to objects and structures.
Multiattack. The black oak makes two attacks with its Dark Hammer.
Dark Hammer. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 10 (1d12 + 4) bludgeoning damage and 4 (1d8) radiant damage.
Big Barrel. Ranged Weapon Attack: +5 to hit, range 60/90 ft., one target. Hit: 11 (2d8 + 2) radiant damage.