Pyxis of Pandemonium is a rare Artifact card from Theros (THS), collector number 220. Current market price: $0.28 (foil $2.37), TCGplayer market prices via Scryfall.
{T}: Each player exiles the top card of their library face down. {7}, {T}, Sacrifice this artifact: Each player turns face up all cards they own exiled with this artifact, then puts all permanent cards among them onto the battlefield.