Divine Serpent Geh

Divine Serpent Geh costs {x} to cast, where {x} is the total amount of life points you have.
Divine Serpent Geh power and toughness are
equal to the total amount of life points that the
oponnent with the highest amount of life has.
You can't lose the game and your opponents can't
win the game.
If Divine Serpent Geh leaves the battlefield, you
lose the game.