Noah, Secret Santa

{1}{w}{w}{g}Secret—(From your hand, you can put this card secretly underneath any card. Once per turn; you may move it to another card. If it get's noticed by an opponent, at the beginning of your next upkeep; you have to pay it's secret cost. If you can't, you lose the game.)
When this card is noticed, create X elf creature tokens with power and toughness of X/X. X is equal to the amount of cards this card was underneath.