War Effort is a uncommon Enchantment card from Tarkir: Dragonstorm (TDM), collector number 131. Current market price: $0.15 (foil $0.29), TCGplayer market prices via Scryfall.
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.