Anti-GMX Final Experiment

Activate only if you control a "GMX" monster. Once per turn, when your opponent activates a monster effect on the field (except during the Damage Step): You can excavate the top 5 cards of your Deck, then if you excavated a "GMX" card(s), negate that activated effect, also place all the excavated cards on the top or bottom of the Deck in any order.

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