Apparently I never got around to clearing Dark Knight. I probably just assumed I didn't have a team because I don't play devils or physical, but so many things randomly have Devil that it was easy to throw together a Kalloween team for it. I'll have to do the coin version later too.
It pains me how almost good Gravis is. HP sticks are almost always good to have, and a sub that fills a bind clear slot while also being a heartbreaker has so much potential. His awakenings are trash though (not even full bind immunity, ugh) and clearing only a single turn of bind isn't actually that useful. The idea of a bind clearing heartbreaker still sounds incredible on paper, but they were waaaay too conservative with him.