"It's a simple game, Jenny," Henry couldn't help but smile as he explained it, "I've cast a spell to switch our bodies. One set of keys unlocks the locker with the reversal spell. The other set of keys will unlock a locker with a finishing spell that will make the swap permanent. Even I don't know which locker is which or which set of keys is which. That's the fun of the game!"
Henry really didn't care about the outcome. He just enjoyed these sorts of games. If he got his body back, he could play again with someone else. If he didn't, there were other games to be played!