Cheapest priced copy (Commander Masters): $0.35 at Card Kingdom, near mint, their price list as of .
Ravaging Blaze 
Instant · Uncommon · Magic Origins · #159
Ravaging Blaze deals X damage to target creature.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, Ravaging Blaze also deals X damage to that creature's controller.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Masters | 250 | Uncommon | $0.35 | $0.49 |
| Magic Origins | 159 | Uncommon | $0.35 | $0.49 |
3 rulings from Wizards of the Coast
- 22 June 2015If the creature becomes an illegal target by the time Ravaging Blaze tries to resolve, Ravaging Blaze won’t resolve and none of its effects will happen. No damage will be dealt to the creature or its controller.
- 22 June 2015Ravaging Blaze targets only the creature. It doesn’t target any player, even if the spell mastery ability applies.
- 22 June 2015Check to see if there are two or more instant and/or sorcery cards in your graveyard as the spell resolves to determine whether the spell mastery ability applies. The spell itself won’t count because it’s still on the stack as you make this check.