[Coda]

Only ultimate evolutions can be reversed -- normal evolutions through Evo Fusion are strictly one-way.

Reversing an ultimate evolution is straightforward: feed the monster a Rubylit, a Sapphilit, an Emelit, a Topalit, and an Amelit.

If this causes the monster's active skill to change, it will revert to rank 1. Awoken skills, on the other hand, are preserved. If you have a monster with awoken skills, and you de-evolve it, it still knows how many awoken skills it's supposed to have even if the old form doesn't have as many. If you then ultimate-evolve the monster again (either into the same form or into a different form) then the monster will have the same number of unlocked awoken skills as it had before.