Quote from schnerbst »Well, i don't think Felidar Sovereign is unfair in powerlevel but I do think it is extremely boring. It is either a Card that does nothing or a card that just ends the game. So the real question to ask yourself is not "is this unfairß" but rather "is this fun?". If you think it is, go ahead and try it out. But if you have a regular playgroup and people there might not like having upkeep triggers abruptly ending games, maybe thats respectable too.