(Sulfurous Marsh isn't a spell.)
Sulfurous Marsh enters the battlefield tapped unless you reveal a basic land card from your hand.
All creatures have Plainswalk.
: Add to your mana pool. If you played a land this turn, Add to your mana pool instead.
: Add 
to your mana pool. If you played a land this turn, Add 
to your mana pool instead.
