Riverrun, Lords of the Trident

Riverrun, Lords of the Trident enters the battlefield tapped.
{t}: Add {u} or {r} to your mana pool.
{u}{r}{t}: Riverrun, Lords of the Trident deals 2
damage to target creature, and you draw a card.
The Tully castle looked like a great stone ship with its
prow pointed downriver. Its sandstone walls were
drenched in red-gold light, and seemed higher and
thicker than Jaime had remembered.