Heavy Shinobi is the main boss of the Press Garden Zone of Sonic Mania and a member of the super robots team with the stupid name.
He's quick and fast, but his main gimmick is turning you into an ice block. Funny enough, I don't think this attack left you without rings.
So while he was annoying to hit, only really bad players would fall against him. But I had my fair share of fun in this boss battle.