>>34680970Technically you could run Dawn Wings Necrozma as your sixth and not have it overlap thanks to species clause
That said, I'd love a Dark/Flying or Ghost/Flying bat with a big focus on draining moves, maybe with an ability that buffs them like Strong Jaw. Add in some new bloodsuck move only it gets, and you got a top tier mon right there. Maybe base it off of a spectral bat in terms of appearance.