You can hack Super Mario Bros. by using the various "Warp Zones" found in some of the levels. In Super Mario Bros. 3, this functionality was changed to require whistling at the console (also known as "catcalling").

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You can hack Super Mario Bros. by using the various "Warp Zones" found in some of the levels. In Super Mario Bros. 3, this functionality was changed to require whistling at the console (also known as "catcalling").