Underwlord Triburaty

Underworld Tributary comes into play tapped
unless you revel a Raven or Spirit card from your
hand. (A Raven is cards named Crow or Raven, is
so in the art, or makes tokens that are so in art,)
{t}: Add {w} or {b}.
{t}: Add one man of any color to your mana pool.
This may only be used to cast a Raven or Spirit
spell.
"No other God interfere with the ferrman's ways, and
only those he favors can fly up from the Tartyx river."