Cheapest priced copy (March of the Machine): $0.35 at Card Kingdom, near mint, their price list as of .
Searing Barb 
Sorcery · Common · March of the Machine · #163
Searing Barb deals 2 damage to any target. If it's a creature, it can't block this turn. Incubate 1. (Create an Incubator token with a +1/+1 counter on it and "{2}: Transform this token." It transforms into a 0/0 Phyrexian artifact creature.)
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| March of the Machine | 163 | Common | $0.35 | $0.49 |