Artifact, XX (0) Chalice of the Void comes into play with X charge counters on it. Whenever a player plays a spell with converted mana cost equal to the number of charge counters on Chalice of the Void, counter that spell.
Illus. Mark Zug
To have it come into play with 3 counters, X must be 3, which means you have to pay {3}{3} or {6} mana. You pay twice of whatever value you want X to be. [Mirrodin FAQ 2003/10/01]
It only checks the number of counters on this card at the time the spell is being played. Changing the number of counters after that will not change the outcome. [Mirrodin FAQ 2003/10/01]
If it has zero counters on it, then it triggers for spells of cost {0}. [Mirrodin FAQ 2003/10/01]
It has to be in play at the end of the playing of a spell to trigger. If you sacrifice it during the playing of a spell, it will not trigger. [Mirrodin FAQ 2003/10/01]
Mirrodin
(Rare)