A Banned Card is a card, or sets of cards, that were not usable in competitive brawling formats. While there were not any strictly banned cards in North American formats (i.e. Baku-Con and the Bakugan Battle League), the Japanese official brawling scene had some restrictions, such as restricting certain Gate Cards, and Ability Card combinations. 
There were no major restrictions in the North American scene. The only restriction was during the 2010 BakuCon, where HSP Cards were limited to only cards with positive attribute bonuses.
For the Japanese official brawling events, there were some restrictions on cards that could be used in play.
The following Gate Cards are banned from being used at Sega events:
Both of these cards have the effect "Lowest G-Power wins".
Ability Card combinations
Brawlers may not have any combination of two or more of the following Red Ability Cards in their deck at Sega events:
Brawlers may not have any combination of two or more of the following Green Ability Cards in their deck at Sega events:
All of the listed Green Ability Cards have effects that prevent the opponent from rolling their Bakugan until a specific condition is met.
Fixing card text
To be used at Sega events, the card Flare Trinity would have to have its text slightly altered.
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