I think " Black Nika " in kids fear sort of confirms it.
Blackbeard having darkness fruit.
Yeah definitely 100%. Yami was said to the be the most evil fruit, implied to have sentience and thus chose Blackbeard directly, sought him out.
Can't wait for mr 3 sword style, the "hunter of blacks" to fight "Black Nika Beard" down the line lmfao.
Also Oda trying to turn Sanji evil with "stealth black" and thus black hair, Oda whyyyyyy?



