Groxx, Trash Tinkerer

{w}{b}: Return target artifact from your graveyard to your hand.
{u}{r}: Create two 1/1 colorless Thopter artifact creature tokens with flying.
{b}{g}, Sacrifice an artifact: Draw two cards.
{g}{u}: Target artifact gains hexproof until end of turn.
{w}{r}, {t}: Target creature gets +X/+0 until end of turn where X is the number of artifacts you control.