Gideon's Triumph is a uncommon Instant card from War of the Spark (WAR), collector number 15. Current market price: $0.16 (foil $0.33), TCGplayer market prices via Scryfall.
Target opponent sacrifices a creature of their choice that attacked or blocked this turn. If you control a Gideon planeswalker, that player sacrifices two of those creatures of their choice instead.