Cloudrift Palace

When Cloudrift Palace enters the battlefield, sacrifice it unless you pay {w}, and return a land you control to your hand.
{t}: Add {w}{w} to your mana pool.
{t}: You may play an additional land this turn. Cloudrift Palace doesn't untap during your next untap step. Activate this ability only once per turn.
When Cloudrift Palace leaves the battlefield, search your library for a plains, and
put it onto the battlefield tapped.