You can only control 1 Gravekeeper's Chief at a time. Your Graveyard is unaffected by Necrovalley. When this card is Tribute Summoned, you can Special Summon 1 Gravekeeper's monster from your Graveyard.
NM-Mint 1st Edition - $0.50
Lightly Played 1st Edition - $0.50
Moderately Played 1st Edition - $0.40
Heavily Played 1st Edition - $0.40
Damaged 1st Edition - $0.30
NM-Mint 1st Edition Non English - $0.50
Lightly Played 1st Edition Non English - $0.50
Moderately Played 1st Edition Non English - $0.40
Heavily Played 1st Edition Non English - $0.40
Damaged 1st Edition Non English - $0.30