Three trailers have been shown of Super Smash Bros. Brawl so far. The original trailer revealing Solid Snake as a playable charater was shown at E3 2006 on May 11, 2006. The second trailer revealing Fox returning as a character was shown at the Nintendo World 2006 convention in December. The third trailer revealing Sonic as a playable charater was shown as the october 10, 2007 Nintendo Press Conference.
E3 Video
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Nintendo World Video
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Nintendo Press Conference Video
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Subspace Emissary Trailer
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