Super Mario Crossover is basically Super Mario Bros. with a selection of NES characters available in addition to the Italian Stallion; they all control more or less like they did in their respective games, and they bring the classic tracks. Some cleverness is imbued in how they respond to fire-flowers and mushrooms, and the rest of the game is SMB down to the tiles, except you can interact with these tiles a bit differently. Subtle things like jumping height and the prerequisites for breaking bricks will jump out at you, carefully built gauntlets will unfurl as hackable, the relevance of four-decimal floating point values will pop out as the underlying soul of the game design you thought you knew growing up.
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