Flapple

gigantimax {7}{g}{g}:
(if this creature is not gigantimaxed, you may pay {5}{g}{g} and this creature becomes gigantimaxed. when you gigantimaxed this creature, double its power and toughness)
When Flapple enters the battlefield, each player gains four times X life
when Flapple dynamaxes, each opponent loses X life where X is half of all players life total