Prismatic Spray

Rainbow Affinity (Prismatic Spray costs {w} less to
cast if you control a white permanent, {u} less to cast
if you control a blue permanent, {b} less to cast if you control a black permanent, {r} less to cast if you
control a red permanent, and {g} less to cast if you
control a green permanent.)
As you cast spells from your hand this turn,
they gain cascade.