Double Hero Attack is a Quick-Play 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, Double Hero Attack is Unlimited.
YGOPRODeck lists Double Hero Attack for these formats: Duel Links, TCG, OCG, Master Duel.
Double Hero Attack belongs to the Elemental HERO archetype—use that tag when searching for engine pieces and tech options.
A listed print of Double Hero Attack appears in Duel Power (DUPO-EN005) at Ultra Rare rarity.
Among markets shown on this page, the lowest listed snapshot for Double Hero Attack is about $0.19 on Cardmarket (prices change frequently).
