Phantom Ghost Yamori

Phantom Ghost Yamori (幻幽鬼 やもり) is the third boss from The Ninja Warriors Again.

Details
Phantom Ghost Yamori appears as a tall, slim ninja wearing a skull mask and large claws. He attacks with a quick combo up close and a dashing attack from a distance. Every once in a while he will jump into the tv monitors in the background and drop bombs in the arena. He can also turn invisible to blend with the background, though he can still be hit during it.

In the original SNES version of the game he is the only boss who fights alone, while in The Ninja Saviors: Return of the Warriors he is helped by regular enemies just like the other bosses.