Mat'Selesnya, Parun of Light

Flash
At the beginning of your upkeep, you may pay {g/w}{g/w}, if you do, spells in your hand gain convoke until the end of turn. (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
{g}{w}, {t}: Populate (Create a token that's a copy of a creature token you control.)