Selene, Prism Weaver

{t}: Add one mana of any color.
Whenever you cast a multicolored spell, untap Selene, Prism Weaver.
Whenever you cast your first spell each turn, you may pay {w}{u}{b}{r}{g}. If you do, you may cast a nonland card with converted mana cost 5 or less from your hand without paying its mana cost.
Her rainbows refract infinite possibility.