Endless Swarm is a rare Sorcery card from Saviors of Kamigawa (SOK), collector number 129. Current market price: $1.64 (foil $18.01), TCGplayer market prices via Scryfall.
Create a 1/1 green Snake creature token for each card in your hand. Epic (For the rest of the game, you can't cast spells. At the beginning of each of your upkeeps, copy this spell except for its epic ability.)