Dark Scheme is a Normal Trap Card.
Trap Cards are normally Set first and can be activated on a later turn, often in response to an action.
On the current TCG and OCG Forbidden & Limited lists tracked here, Dark Scheme is Unlimited.
YGOPRODeck lists Dark Scheme for these formats: Duel Links, Common Charity, TCG, OCG, Master Duel.
A listed print of Dark Scheme appears in Gates of the Underworld Structure Deck (SDGU-EN031) at Common rarity.
Among markets shown on this page, the lowest listed snapshot for Dark Scheme is about $0.20 on TCGPlayer (prices change frequently).
