Labile Incantation

You may cast Labile Incantation as a copy of any spell on the stack, except its name is still Labile Incantation.
Whenever a player casts a spell, if Labile Incantation is on the stack, Labile Incantation becomes a copy of that spell, except its name is still Labile Incantation. You may choose new targets for it.
Its fluidity is its greatest strength and weakness.