Okay, so today I had a weird interaction. My opponent played a temporary lockdown. I exiled it later with my Kaya, Intangible Slayer.
This produces a 1/1 spirit token, that should theoretically exile itself. This did however not happen in Arena. Why is that?
Is it a bug or is there a rule that I don’t know?
To add to this, tokens have no mana cost (mana value 0) unless they are copies, in which case they have the mana cost of whatever they are copying. (There are a few exceptions, like embalm/eternalize, but they’re always explicitly called out)