The Seal of Orichalcos has an effect that "Once per turn, this card cannot be destroyed". However, if Mystical Space Typhoon is activated in response to playing this card, it can pop the card. Is this a bug or does Mystical Space Typhoon somehow activate before the Seal of Orichalcos does?

That just shows that it's indestructible once per turn because of itself.

The popup shows the card that prevents it from being destroyed.

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Since mst is chained it resolve before seal
and like all other Field/Continuous/equip its continuous effect are not applied before it resolves
so it destroy seal before it gain its protection effect

Since mst is chained it resolve before seal
and like all other Field/Continuous/equip its continuous effect are not applied before it resolves
so it destroy seal before it gain its protection effect

Oh. It seems I misread. "pop the card." [:lol:]

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