Vexing Puzzlebox is a mythic Artifact card from Commander Legends: Battle for Baldur's Gate (CLB), collector number 343. Current market price: $8.90 (foil $10.46), TCGplayer market prices via Scryfall.
Whenever you roll one or more dice, put a number of charge counters on this artifact equal to the result. {T}: Add one mana of any color. Roll a d20. {T}, Remove 100 charge counters from this artifact: Search your library for an artifact card, put that card onto the battlefield, then shuffle.
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