There are tons of imaginative assists out there in the world of anime fighters. Here’s a few for example:
Nitroplus Blasterz: An assist summons a black smog that when it hits you, you can’t jump and take extra damage.
DBFC: TONS. Where do I even begin?
Kuroneko: Places a defensive seal on you that eats any one attack and then explodes leading for combo extensions.
Holo:Heals and regens meter in a specific range.
Kazari: Timed 3 second gun shots that have specific requirements to achieve.
Llen: A negative edge assist that you can kick which will attack the enemy when they are within range.
I seriously could go on and on about the unique anime assists out there. If you want to(shameless plug), check out my assist breakdown videos. Not only do they show assists that you don’t normally see in regular fighting games, but they have a very unique take on even the simplest of fireball/beam assists we know of today. Very creative stuff.