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 Unlimited - $3.40
Near Mint 1st Edition - $4.10
Lightly Played Unlimited - $2.70
Lightly Played 1st Edition - $3.30
Moderately Played Unlimited - $2.20
Moderately Played 1st Edition - $2.70
Heavily Played Unlimited - $1.70
Heavily Played 1st Edition - $2.10