Mephitic Vapors is a common Sorcery card from Guilds of Ravnica (GRN), collector number 76. Current market price: $0.11 (foil $0.39), TCGplayer market prices via Scryfall.
All creatures get -1/-1 until end of turn. Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)