Land As Primal Beyond enters the battlefield, you may reveal an Elemental card from your hand. If you don't, Primal Beyond enters the battlefield tapped. {T}: Add {1} to your mana pool. {T}: Add one mana of any color to your mana pool. Spend this mana only to cast Elemental spells or activate abilities of Elementals.1
Illus. Mark Tedin
4/1/2008: You can use the mana produced by Primal Beyond's last ability to pay an alternative cost (such as evoke) or additional cost incurred while casting an Elemental spell. It's not limited to just that spell's mana cost.
4/1/2008: The mana can't be spent to activate activated abilities of Elemental sources that aren't on the battlefield (such as the reinforce ability of an Elemental card in your hand).