Marco of the Forest Staff

Partner with Lilith, The Dark Hyacinth
At the beginning of each upkeep, that player exiles the top card of their library. For as long
as they remain exiled, you may cast them using mana of any color.
At the end of each turn, for each spell you've cast without color restriction, add that much mana.
{t}, {u}{r}{g}{x}: Creatures you control become X colors.