The Rack is a special Artifact card from Time Spiral Timeshifted (TSB), collector number 113. Current market price: $3.98 (foil $57.50), TCGplayer market prices via Scryfall.
As this artifact enters, choose an opponent. At the beginning of the chosen player's upkeep, this artifact deals X damage to that player, where X is 3 minus the number of cards in their hand.