Earthshattering Event is a Continuous 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, Earthshattering Event is Unlimited.
YGOPRODeck lists Earthshattering Event for these formats: Duel Links, TCG, OCG, Master Duel.
A listed print of Earthshattering Event appears in World Superstars (WSUP-EN042) at Prismatic Secret Rare rarity.
Among markets shown on this page, the lowest listed snapshot for Earthshattering Event is about $0.35 on TCGPlayer (prices change frequently).
