wait, i thought you only got the accuracy and damage enchants from the sun school trainer, the only place i know is from the archivist in the district of the stars...(i may be wrong taking the fact i haven't looked at a sun trainer for a while)
Haha! I loved these spells when I first saw them, too!
Yes, they are mutation spells, and you must own the original kraken spell to mutate it.
I am not really sure where you can get the actual spell, but I know that they sell mutate spells at the bazaar! I have seen many mutate spells there, but so far have only seen two kraken mutate spells, and they are expensive.
So, I would just stick to the original kraken spell for now: it's very powerful, though! :D