Alright, random game pitch:
A 1v1 3d character fighter, but... instead of having a moveset, each character has a unique deck that can be customized to your benefit, with character specific cards(and character specific “finale” finisher cards) and then generic stuff like weapons. Gameplay would be turn based with multiple chances of interrupting your opponent and responding to things they do, not unlike how Yugioh does it with chain links.
That’s the main premsie, and while I haven’t actually done any work on a theoretical game, I have character concepts ready to go and some ideas for the actual gameplay and balancing.