Basilica Guards is a common Creature — Human Soldier card from Gatecrash (GTC), collector number 5. Current market price: $0.16 (foil $0.69), TCGplayer market prices via Scryfall.
Defender Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)