Cheapest priced copy (Tarkir: Dragonstorm): $0.35 at Card Kingdom, near mint, their price list as of .
War Effort 
Enchantment · Uncommon · Tarkir: Dragonstorm · #131
Creatures you control get +1/+0.
Whenever you attack, create a 1/1 red Warrior creature token that's tapped and attacking. Sacrifice it at the beginning of the next end step.
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Tarkir: Dragonstorm | 131 | Uncommon | $0.35 | $0.49 |