Activate only if both a "Gravekeeper's" monster and "Necrovalley" are on the field. Neither player can Special Summon monsters, except "Gravekeeper's" monsters. If either a "Gravekeeper's" monster or "Necrovalley" is not on the field, destroy this card.
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.
All "Gravekeeper's" monsters gain 500 ATK and DEF. Cards in the Graveyard cannot be banished. Negate any card effect that would move a card in the Graveyard to a different place. Negate any card effect that changes Types or Attributes in the Graveyard.
While a "Gravekeeper's" monster(s) and "Necrovalley" are both on the field, monsters your opponent controls lose 500 ATK/DEF. Once per turn, during the Main Phase, if you control no card in your Field Zone: You can activate 1 "Necrovalley" directly from your hand or GY. If this card in your possession is destroyed by an opponent's effect and sent to your GY: You can Set 1 "Necrovalley" Spell/Trap directly from your Deck, except "Necrovalley Temple".
Activate 1 of these effects.
â—Ź Add 1 "Gravekeeper's" monster from your Deck to your hand.
â—Ź Immediately after this effect resolves, Normal Summon 1 "Gravekeeper's" monster.
You can only activate 1 "Necrovalley Throne" per turn.