(Flooded Catacomb isn't a spell.)
When Flooded Catacomb enters the battlefield, sacrifice it unless you pay 3 life.
, : Tap target artifact with converted mana cost X or less.
, : Add to your mana pool.
, 
: Tap target artifact with converted mana cost X or less.
, : Add 
to your mana pool., : Add to your mana pool.
