Imperial Iron Wall is a Continuous 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, Imperial Iron Wall is Unlimited.
YGOPRODeck lists Imperial Iron Wall for these formats: Common Charity, Edison, TCG, OCG, Master Duel.
A listed print of Imperial Iron Wall appears in Legendary Collection 4: Joey's World Mega Pack (LCJW-EN298) at Ultra Rare rarity.
Among markets shown on this page, the lowest listed snapshot for Imperial Iron Wall is about $0.15 on TCGPlayer (prices change frequently).
