Tibalt's Gambit

As an additional cost discard any number of
nonland cards from your hand, note the
combined converted mana cost of all cards
discarded in this way.
Reveal the top card of your library and add it to
your hand, then you may repeat this effect. If the combined converted mana cost cards of all cards
added to your hand with Tibalt's Gambit exceeds
the noted amount you loss the game.