Coercive Portal is a mythic Artifact card from Conspiracy (CNS), collector number 56. Current market price: $9.70 (foil $16.00), TCGplayer market prices via Scryfall.
Will of the council — At the beginning of your upkeep, starting with you, each player votes for carnage or homage. If carnage gets more votes, sacrifice this artifact and destroy all nonland permanents. If homage gets more votes or the vote is tied, draw a card.