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: Target opponent mills a card, then repeats this process until a creature card or X cards have been put into their graveyard this way, whichever comes first. If one or more creature cards were put into that graveyard this way, sacrifice this artifact and put one of them onto the battlefield under your control. X can't be 0.No reference price for this printing yet: not enough stores to make an average.
Run a comparison: we query the stores live, it may have arrived this morning.
If an effect like that of Leyline of the Void prevents cards from being put into your opponent’s graveyard, the process described in the first sentence of Helm of Obedience’s effect will never stop. Your opponent’s entire library will be exiled, even if X is 1.
2008-10-01 · Wizards of the CoastYou put the creature card onto the battlefield even if you can’t sacrifice Helm of Obedience (because it’s left the battlefield by the time its ability resolves, for example).
2008-10-01 · Wizards of the Coast
Player's Cards and Collectibles · Condition HP
