I'm making a creature with the rabbit as a base, and I was wondering if anyone knew how to give it appropriate combat data and such to make him actually fight. He will eventually need to be able to cast spells. Is this even possible?

Hmm. I think you can cast spells without animations (because they can be scripted) but I'm not sure you can do combat unless animations for it already exist.

Keep your rabbit away from me. Sounds like it has a mean streak a mile wide.

The rabbit is really a pikachu He lurvs you.
Anyhow, I suppose it wouldn't be such a bad thing if he just cast lightning spells, I was just hoping I could have him use "Tackle" and such as well.

Well, you could always make the rabbit immune to falling damage and use pushactoraway or moveto to flop him up and down as if he's jumping when he casts lightning.

I'm not an expert but that's the kind of Red Sanford method I would do. I like a little comedy in my mod though here and there.

(Horrible Scots accent) Och, laddie, that cave is guarded by a creature so foul, so cruel that no man yet has fought wi it an lived! Bones o full fifty men lie strewn abou' it's lair!

"You MANKY SCOTS GIT! I almost soiled me armor I was so scared!"

@ OP, if this is going where it's logical conclusion seem to be, I hope you figure it out!