Necrovalley [AP04-EN003] Ultimate Rare Animal Kingdom Pirates you can substitute this card

you can substitute this card for a Tribute(s)

Set: Crimson Crisis Card type: Quick Play Spell Rarity: Super Rare Attack: 0 Defense: 0 Tribute 1 face-up "Kuriboh"

Set: Phantom Darkness Card type: Effect Monster Rarity: Ultra Rare Attack: 2800 Defense: 2200 Once per turn

And with the coming of this horror

Necrovalley [AP04-EN003] Ultimate Rare Animal Kingdom Pirates you can substitute this cardSet: Astral Pack 4 Card type: Field Spell Rarity: Ultimate Rare Attack: 0 Defense: 0 All "Gravekeeper's" monsters gain 500 ATK and DEF. Cards in either player's Graveyard cannot be banished. Negate any card effect that would move a card in the Graveyard, other than itself, to a different place.