Base: Super Mario Bros. · PC-88 / Sharp X1 · 1986 · Total Conversion
Creator: Hudson Soft
An officially licensed port of Super Mario Bros. developed by Hudson Soft for Japanese home computers, featuring new levels, new items, and scrolling replaced by screen-by-screen transitions due to hardware limitations.
Super Mario Bros. Special was not a ROM hack in the fan modification sense — it was a legitimate licensed port commissioned by Hudson Soft for the NEC PC-88 and Sharp X1 home computers in 1986. Hudson lacked the hardware capability to replicate the NES's smooth horizontal scrolling, so they replaced it with a screen-flip technique that displayed the level one screen at a time, fundamentally altering the feel of Mario's movement. New items were added — a hammer from Donkey Kong, a stopwatch that froze enemies — and entirely new levels were designed. The result was a curiosity: officially sanctioned, commercially released, and sufficiently different from the original to feel like a distinct and somewhat broken alternative universe version of the game.