Altar of Magical Control

{x}{u}{r}: Choose target spell with converted mana
cost X or less. You may choose new targets for
that spell. This costs {1} less to cast for each
Shrine you control.
Whenever you play a spell, if it has converted
mana cost equal to the number of Shrines you
control and it's your first spell this turn, copy it.
You may choose new targets for the copy.