Super Mario Bros. Huge New Glitch: The "Holy Grail" found after 40 years. No hacks: just technical mastery. ( ...
"This glitch means we choose what code the game executes. You can basically make the game do whatever you want" ...
Super Mario Bros. speedrunners have discovered a major glitch in the game that allows players to manipulate code on the fly.
By meeting a specific set of conditions, including activating Second Quest, ACE can be achieved in Super Mario Bros. 1.