Erratic Explosion is a common Sorcery card from Onslaught (ONS), collector number 201. Current market price: $0.18 (foil $2.20), TCGplayer market prices via Scryfall.
Choose any target. Reveal cards from the top of your library until you reveal a nonland card. Erratic Explosion deals damage equal to that card's mana value to that permanent or player. Put the revealed cards on the bottom of your library in any order.