"Onslaught of the Fire Kings" have the text "You can only activate 1 "Onslaught of the Fire Kings" per turn.". But when I duel, the rival played it, I countered by "Solemn Warning". But after that, he played the second one in the same turn. Please fix it.
Thank you.

the activation was negated, so it doesn't count as "Activated".

Scratch all that I just said.

Checked over all rulings of cards, if a card has been negated you can activate another copy even if it says once per turn.

http://yugioh.wikia.com/...ulings:Spell_Power_Grasp 

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You activated it still, it doe not matter that it was negated. You can only ever use a card that says once per turn, once per turn no matter what. (Unless they come out with a card that says you can ignore this.)

Do you have the replay so we can check for a bug.

Just changed my post above please refer to it.

Was looking at an old source when I wrote my first draft.

Also that video was not bad, but it could do with adding in sources, as you can say anything in a youtube video. But in this case it was correct. I was just looking at a old discussion when I made my first post.

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This is the replay that "Onslaught of the fire kings" has been activated twice in the same turn.

Leanhluudan, please read the comments above, you can activate a spell that says once per turn, twice if its Activation is negated.

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