You can only control 1 face-up "Gravekeeper's Chief". Your Graveyard is unaffected by "Necrovalley". When this card is Tribute Summoned: You can target 1 "Gravekeeper's" monster in your Graveyard; Special Summon that target.
Near Mint Unlimited - $0.40
Lightly Played Unlimited - $0.40
Moderately Played Unlimited - $0.30
Heavily Played Unlimited - $0.20
Damaged Unlimited - $0.20