How Speedrunners Break Games

Short4,626 views35 s6 November 2026

Games check for walls in steps, not continuously, so a fast enough object passes straight through one. Speedrunners build their runs on exactly those gaps.

The script

A speedrunner can finish a game in under a minute... without playing most of it.

Not by being fast. By breaking the code.

Every game checks for walls in steps... not continuously.

Move fast enough, and you're on one side... then the other.

That's a tunnel. Speedrunners call it a clip.

In Mario sixty four, the speed cap only checks forward speed.

Jump backwards, and the cap never applies.

In Super Mario World, one glitch skips straight to the credits.

None of it is cheating. The game is doing what the code says.

So the next time a run looks impossible...

The facts, checked

  • Collision detection runs per frame or per physics step, not continuously; a fast enough object can pass through geometry between checks (tunnelling).
  • Super Mario 64's backwards long jump (BLJ) exploits the speed cap applying only to forward speed, so backward speed can grow without limit.
  • Super Mario World's credits warp uses a glitch in the sprite table to jump straight to the ending, enabling 0-exit runs.
  • These are implementation bugs, not intended mechanics; speedrun categories define which glitches are allowed. Re-check the record times before naming one.

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