Ioyass, the Regenerator

At the beginning of your upkeep, you gain X life
where X is the amount of creatures you have on
the battlefield and each player may scry 1, if they
do, you scry 1 for each player that does.
{x}{w/u}, {t}: You can return a creature with X or
less from your graveyard to the battlefield, it
gains flying and hexproof until the end of your
next turn. X is equal to Ioyass's Power.
When Ioyass dies return a creature with lesser
power to the battlefield.