Watch runs like this LIVE at   / darbian  

World record from 10/5/2016 10/20/2017, played on a real NES. The first 4:56 achieved by a human a time that was considered nearly impossible just a few weeks ago.

Previous record by Kosmicd12:    • Super Mario Bros. Speedrun in 4:57.19...  
Leaderboard: http://www.speedrun.com/smb1
Twitch VOD:   / 93252556  
Tutorial video:    • [Tutorial] Super Mario Bros. any%   This will answer most (but not all!) of the questions asked in comments!