When Dragonskull Shores enters the battlefield, sacrifice it unless you pay .
: Add or to your mana pool.
Put Dragonskull Shores on top of your library: Add to your mana pool.
: Return Dragonskull Shores to its owner's hand.
.
: Add 
or to your mana pool.
to your mana pool. : Return Dragonskull Shores to its owner's hand.
