Shelldock Mesa enters the battlefield tapped unless you pay 2 life.
: Add or to your mana pool.
Put Shelldock Mesa on top of your library: Add to your mana pool.
, Sacrifice Shelldock Mesa: Add to your mana pool.
: Add 
or 
to your mana pool.
to your mana pool. , Sacrifice Shelldock Mesa: Add 
to your mana pool.
