When a Spell Card, Trap Card, or monster effect is activated, while both a "Gravekeeper's" monster and "Necrovalley" are on the field: Negate the activation, and if you do, destroy it. You can only activate 1 "Imperial Tombs of Necrovalley" per turn.
Near Mint / Lightly Played Unlimited - $2.50
Moderately Played Unlimited - $2.50
Heavily Played Unlimited - $2.00
Damaged Unlimited - $1.50
Near Mint / Lightly Played 1st Edition - $4.50
Moderately Played 1st Edition - $4.00
Heavily Played 1st Edition - $3.50
Damaged 1st Edition - $3.00