: Search your library for a Island or Swamp card and put it onto the battlefield tapped. Shuffle your library, then put Sea Underground on top of it.
, Sacrifice Sea Underground: Add to your mana pool.
: Search your library for a Island or Swamp card and put it onto the battlefield tapped. Shuffle your library, then put Sea Underground on top of it., Sacrifice Sea Underground: Add 
to your mana pool.
