As Frostboil Snarl enters, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters tapped.
: Add or .
As Frostboil Snarl enters the battlefield, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters the battlefield tapped.
: Add or .
"We're on the Thames. The last great Frost Fair. 1814, February the 4th."
—The Twelfth Doctor