Galvanoth
Creature — Beast
At the beginning of your upkeep, you may look at the top card of your library. You may cast it without paying its mana cost if it's an instant or sorcery spell.
It chews open Mirrodin's husk and feeds on the outpouring of energy.
Kev Walker
Mirrodin Besieged (MBS)
• #62Rulings
You may pay additional costs, such as kicker costs, of the instant or sorcery card.
(wotc • 2011-06-01)
If the card has an X in its mana cost, you must choose 0 as its value.
(wotc • 2011-06-01)
If the card you look at isn’t an instant or sorcery card, it remains on top of your library. You don’t reveal it.
(wotc • 2011-06-01)
If the card has any mandatory additional costs, as Kuldotha Rebirth does, you must pay them in order to cast the spell.
(wotc • 2011-06-01)
Rulings
You may pay additional costs, such as kicker costs, of the instant or sorcery card.
(wotc • 2011-06-01)
If the card has an X in its mana cost, you must choose 0 as its value.
(wotc • 2011-06-01)
If the card you look at isn’t an instant or sorcery card, it remains on top of your library. You don’t reveal it.
(wotc • 2011-06-01)
If the card has any mandatory additional costs, as Kuldotha Rebirth does, you must pay them in order to cast the spell.
(wotc • 2011-06-01)