Super Mario Brothers: The Lost Levels is a special version of 
Nintendo's 
Super Mario Bros. SMB2:LL does not have a two-player game. Instead, one may play as Mario or as Luigi. The game is a little harder than the original Super Mario Bros, due to a slightly modified game engine, and more difficult levels. It was not released in the 
United States until its inclusion in 
Super Mario All Stars. After that, it was released in 
Super Mario Deluxe, though hidden.
 
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