Museum obtains rare demo of id Software's Super Mario Bros. 3 PC

1990 demo was rejected by Nintendo but led to id's own Commander Keen.

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Museum obtains rare demo of id Software's Super Mario Bros. 3 PC port

Retro - Museum obtains rare demo of id Software's Super Mario Bros. 3 PC port, 1990 demo was rejected by Nintendo but led to id's own Commander Keen

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