Sinnoh, Region of Myth

Sinnoh, Region of Myth enters the battlefield
tapped.
Discover Dialga, Palkia or Giratina.
Discover Darkrai or Cresselia.
Discover Uxie, Mesprit or Azelf.
Discover Heatran or Regigigas.
{t}: Add {w}, {u} or {b} to your mana pool.