Hey there, I've reported this bug in game already, but I wanted to warn players so they don't go through what I went through-

If you are a butterfly player, whatever you do, do not turn into bird form (for the + to cold resist) and then guzzle fairy dust (for the + speed). What happens is that you are no longer treated as a butterfly and it tries to remorph you into a temporary butter. What happens then is that once your temporary butterfly (even though you are already perma butter) wears off, you will still be a butterfly but now you will be grounded - forever- and not able to fly.

However, if this happens to you, you can panacea out of it and rebutter and this seems to fix the issue, but... it will cost you a panacea.