Super Smash Bros. Ultimate is the fastest-selling game in the series on the fastest-selling system this generation - Polygon

Nintendo has sold over three million copies of Super Smash Bros. Ultimate in the game’s first 11 days on the market in the US, making it the fastest-selling game in the series. The Switch itself also continues to sell at a rapid pace.

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Super Smash Bros. Ultimate Is Officially The Fastest Selling Nintendo Game Ever

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Super Smash Bros. Ultimate is the fastest-selling game in the series on the fastest-selling system this generation - Polygon

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Super Smash Bros. Ultimate is the fastest-selling Switch game ever