The Omniscient Trespasser

You may look at your opponent's hand.
Discard a card from your hand: Choose a
nonland card in an opponent's hand with a
converted mana cost of X, where X is the
converted mana cost of the discarded card. That
opponent discards that card and creates a Gift
token. (It's a artifacts with "Sacrifice this artifact:
You gain 1 life.")