Bumping this, because I think it's still a change that needs to be
made. This can also pave the way for gigantamaxing, just as a side
note. We could put gmax item(s) in the cauldron in a similar way as
mega stones, too.
Perhaps we could have this idea, as well as the universal mega
stone, but with a twist. Maybe there would be a rare chance of
obtaining a universal mega stone in treasure boxes or mystery
boxes, but you could boil pokemon specific stones in the cauldron