Necrovalley is a Field Spell Card.
Spell Cards are usually activated from the hand on your turn unless their type gives another timing window.
On the current TCG and OCG Forbidden & Limited lists tracked here, Necrovalley is Unlimited.
YGOPRODeck lists Necrovalley for these formats: GOAT, OCG GOAT, Duel Links, Common Charity, Edison, Speed Duel, TCG, OCG, Master Duel.
Necrovalley belongs to the Gravekeeper's archetype—use that tag when searching for engine pieces and tech options.
A listed print of Necrovalley appears in Astral Pack Four (AP04-EN003) at Ultimate Rare rarity.
Among markets shown on this page, the lowest listed snapshot for Necrovalley is about $0.56 on TCGPlayer (prices change frequently).
