If you and an opponent each have 11 cards in your hand, and you play Trade Hands, would you win because after the card’s effect occurred you had 11 while the opponent had 10, or would the opponent win as soon as the card was played and left your hand?
A: This is a tricky question. At first it seems like you should need to finish the step you were in the middle of (i.e. follow through with the hand swap), before considering the issue of someone meeting the Goal. After due consideration, Andy concluded that we must obey the underlying principle of everything happening instantly in Fluxx. So, while the trade does happen simultaneously, the card must first leave your hand (be played) in order for the trade to happen, therefore, you lose the game the moment the 11th card leaves your hand.