Artifact, 3 (3)
Rare
{X}, {T}: Target player puts the top X cards of his or her library into his or her graveyard.
It counts down your last few moments of sanity.
Illus. Charles Urbach

7/1/2012: If the player has fewer than X cards in his or her library, he or she puts all of them into his or her graveyard.
Legal in Vintage (Type 1)
Legal in Legacy (Type 1.5)
Legal in Extended (Type 1.X)
Legal in Standard (Type 2)
Legal in Classic (MTGO)
Legal in Commander
Legal in Modern