Whimsical Warp

At the beginning of your upkeep, flip a coin.
Heads: Reveal the top card of your library. If it's
a creature card, you may put it onto the
battlefield. If it's not, put it into your graveyard.
Tails: Reveal the top card of your opponent's
library. If it's a creature card, you may put it
onto the battlefield under your control. If it's
not, put it into your opponent's graveyard.