Aqua of the Axis Order

Aqua cost {1} less to cast for each Legendary permanents you control.
Purification - {w/u}{w/u}{t}: Exile target Zombie,
Skeleton, Spirit, or Horror creature.
{1}{t}: Add {u}{u}{u} to your Mana Pool.
{10}: Put target Legendary creature from your graveyard into the battlefield.