Via fusing, I just discovered, one can give the resulting character skill combos; some are unique (unless there are other ways to learn, say, FireLeap), some not. Here are the ones I've found on my current (and only) save:
Toxin + SpawnVine = SpawnPoisonFlower
Fireball + Spawn Vine = SpawnFirePlant
Fireball + Fireball = FlameStrike
Jump + Fireball = FireLeap
Jump + Jump = LongJump
Claws + Claws = Slice
Does anyone have more examples? Nevermind, just found the wiki page:
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