Speedrunning is an anarchic e-sport that, instead of getting skills based on a game's internal rules, often tries to break the rules of the game to get a faster completion time. Everything the game lets you do is allowed, which includes the exploit of glitches. (Yes, there are glitchless categories for other games, for LIMBO however, such a category seems unnecessary.) Most fun is it to compare your running times with fellow speedrunners. To provide a fair comparison, few things must be cleared, so every runner has the same chances.
- The timer starts when you hit the "Start A New Game" option in the menu. To minimize loading times, it is recommend to start a new game without hitting the timer first and when it is loaded, start a new game again and this time hitting the timer - otherwise you might encounter a rather long loading time after choosing the option and the actual start of the game.
- The timer stops on the frame when the boy hits the glass wall. Usually, a speedrun timer ends with the last input a player makes in a game or when the player loses control; in LIMBO however, there is a slight possibility to still die after the last input is made. As such, the impact on the glass was chosen the frame. The time between the last action and reaching the glass wall is not consistent and depends on the setup that was used before. There are strats available how to time your last jump to reach the glass wall with a minimized time loss.