(Plains Sea isn't a spell.)
When Plains Sea enters the battlefield, sacrifice it unless you pay .
, : Tap target artifact with converted mana cost X or less.
: Add or to your mana pool. Plains Sea deals 2 damage to you.
.
, 
: Tap target artifact with converted mana cost X or less.: Add or 
to your mana pool. Plains Sea deals 2 damage to you.
