Yawgmoth's Agenda is a rare Enchantment card from Invasion (INV), collector number 135. Current market price: $0.56 (foil $29.99), TCGplayer market prices via Scryfall.
You can't cast more than one spell each turn. You may play lands and cast spells from your graveyard. If a card would be put into your graveyard from anywhere, exile it instead.