Jinxed Choker is a rare Artifact card from Mirrodin (MRD), collector number 189. Current market price: $2.41 (foil $14.47), TCGplayer market prices via Scryfall.
At the beginning of your end step, target opponent gains control of this artifact and puts a charge counter on it. At the beginning of your upkeep, this artifact deals damage to you equal to the number of charge counters on it. {3}: Put a charge counter on this artifact or remove one from it.