You can only control 1 face-up "Gravekeeper's Chief". Cards in your Graveyard is unaffected by "Necrovalley". When this card is Tribute Summoned, you can Special Summon 1 "Gravekeeper's" monster in your Graveyard.
Near Mint Unlimited - $0.30
Lightly Played Unlimited - $0.30
Moderately Played Unlimited - $0.20
Heavily Played Unlimited - $0.20
Damaged Unlimited - $0.20