Cheapest priced copy (Duel Decks: Knights vs. Dragons): $0.35 at Card Kingdom, near mint, their price list as of .
Jaws of Stone 
Sorcery · Uncommon · Shadowmoor · #97
Jaws of Stone deals X damage divided as you choose among any number of targets, where X is the number of Mountains you control as you cast this spell.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
3 printings · $0.35 to $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Duel Decks: Knights vs. Dragons | 77 | Uncommon | $0.35 | — |
| Duel Decks: Venser vs. Koth | 72 | Uncommon | $0.35 | — |
| Shadowmoor | 97 | Uncommon | $0.35 | $0.79 |
3 rulings from Wizards of the Coast
- 1 May 2008You divide the damage among the targets as you cast Jaws of Stone. Each target must be assigned at least 1 damage.
- 1 May 2008If you control no Mountains as you cast Jaws of Stone, the number of targets must be zero.
- 1 May 2008The amount of damage is locked in as you cast Jaws of Stone. It won’t change, even if the number of Mountains you control changes.