Ready for Intercepting 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, Ready for Intercepting is Unlimited.
YGOPRODeck lists Ready for Intercepting for these formats: GOAT, OCG GOAT, Speed Duel, Duel Links, Common Charity, Edison, TCG, OCG, Master Duel.
A listed print of Ready for Intercepting appears in Battle Pack 3: Monster League (BP03-EN192) at Common rarity.
Among markets shown on this page, the lowest listed snapshot for Ready for Intercepting is about $0.06 on TCGPlayer (prices change frequently).