and Just for people i hope you don't mind i'm gonna list all the cards that a gravekeeper deck would use/co inside with necrovalley
Gravekeeper's Assailant
Attrib: Dark
Type: Spellcaster/Effect
Level:4
Atk: 1500
Def: 1500
You can activate this card's effect only when "Necrovalley" is active on the field. When this card attacks, you can change the battle position of 1 face-up monster on your opponent's side of the field.
Gravekeeper's Cannonholder
Attrib: Dark
Type: Spellcaster/Effect
Level:4
Atk: 1400
Def: 1200
Offer 1 card that includes "Gravekeeper's" in its card name on your side of the field as a tribute to inflict 700 points of Direct Damage to your opponent's Life Points. However, you cannot offer this card or another "Gravekeeper's Cannonholder" with this card's effect. Monsters used for a Tribute Summon or that are offered as Tributes due to other cards' effects are excluded.
Gravekeeper's Chief
Attrib: Dark
Type: Spellcaster/Effect
Level:5
Atk: 1900
Def: 1200
You can only have 1 face-up "Gravekeeper's Chief" on your side of the field at any time. As long as this card remains face-up on the field, your Graveyard is not affected by "NecroValley". When you Tribute Summon this monster, you can Special Summon 1 monster that includes 'GraveKeeper's' in its name from your Graveyard.
Gravekeeper's Curse
Attrib: Dark
Type: Spellcaster/Effect
Level:3
Atk: 800
Def: 800
When this monster is Normal Summoned, Flip Summoned, or Special Summoned, inflict 500 points of Direct Damage to your opponent's Life Points.
Gravekeeper's Guard
Attrib: Dark
Type: Spellcaster/Effect
Level:4
Atk: 1000
Def: 1900
FLIP: Select 1 Monster Card on your opponent's side of the field (regardless of position) and return it to its owner's hand.
Gravekeeper's Spear Soldier
Attrib: Dark
Type: Spellcaster/Effect
Level:4
Atk: 1500
Def: 1000
When this card attacks with an ATK that is higher than the DEF of your opponent's Defense Position monster, inflict the difference as Battle Damage to your opponent's Life Points.
Gravekeeper's Spy
Attrib: Dark
Type: Spellcaster/Effect
Level:4
Atk: 1200
Def: 2000
FLIP: Select 1 monster that includes "Gravekeeper's" in its card name with an ATK of 1500 or less from your Deck and Special Summon it in face-up Attack or Defense Position. The Deck is then shuffled.
Gravekeeper's Vassal
Attrib: Dark
Type: Spellcaster/Effect
Level:3
Atk: 700
Def: 500
The Battle Damage this card inflicts to your opponent's Life Points is treated as the Effect Damage of this card.
Gravekeeper's Watcher
Attrib: Dark
Type: Spellcaster/Effect
Level:4
Atk: 1000
Def: 1000
When your opponent activates a card that includes the effect of making your opponent discard from his/her hand (this does not include the cost of discarding cards), you can activate this card by discarding this from from your hand to the Graveyard. Negate the activation, and effect of the card, and destroy it
Necrovalley
Group: Spell Card
Type: Spell
Icon:Field
As long as this card remains face up on the field, all effects of Magic, Trap, and/or Effect Monster Cards that involve Graveyards are negated and neither player can remove cards in the Graveyard from play. In addition, increase the ATK and DEF of all monsters that includes 'GraveKeeper's' in their card name by 500 points.
A Cat of Ill Omen
Attrib: Dark
Type: Beast/Effect
Level:2
Atk: 500
Def: 300
FLIP: Select 1 Trap Card from your Deck and place it on top of your Deck. If "Necrovalley" is active on the field, you can add the selected card to your hand.
Rite of Spirit
Group: Trap Card
Type: Trap
Select 1 Monster Card that includes "Gravekeeper's" in its card name from your Graveyard and Special Summon it in face-up Attack or Defense Position. This card's activation and effect is not affected by "Necrovalley"
Royal Tribute
Group: Spell Card
Type: Spell
This card can only be activated when your "Necrovalley" is active on the field. Both players must discard all monster cards in their hand to the Graveyard.
Charm of Shabti
Attrib: Earth
Type: Rock/Effect
Level:1
Atk: 100
Def: 100
Discard this card from your hand to the Graveyard to make the damage inflicted to monsters that include "Gravekeeper's" in their card name 0 until the End Phase of the current turn. However, the damage to your Life Points is calculated normally.
(Works like a reverse kuriboh monster's live you take life)