Post
The most famous glitch in speedrunning history: Mario moonwalking up stairs at light speed because the game forgot to cap backwards velocity.
In Super Mario 64, performing a long jump and then holding backwards lets Mario build speed without limit because the game only caps forward velocity, not backward velocity. By repeatedly triggering the long jump animation on stairs or slopes (where the game keeps resetting Mario's position to the ground), runners build up absurd speed values in the hundreds, then redirect that velocity to launch Mario through loading zones, up endless stairs, and past barriers. The BLJ is the foundational glitch of SM64 speedrunning and has been known since the late 90s, yet it remains one of gaming's most iconic exploits.
Example
The endless staircase before Bowser's final fight was designed to be impassable without 70 stars; the stairs literally loop forever. But BLJ lets runners build enough speed on the stairs to clip past the trigger zone and reach the final boss with as few as 0 stars. This single trick defines the SM64 0-star category.
Why it matters
BLJ is the poster child for speedrun glitches: simple to understand, visually hilarious, and game-breakingly powerful. It demonstrates how a single oversight in velocity capping can make an entire game's progression system irrelevant, and it's introduced millions of viewers to speedrunning through GDQ events and YouTube.
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