Mephitic Vapors is a common Sorcery card from The List (PLST), collector number GRN-76. Current market price: $0.37, 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.)