Run Wikia


The B-Tunnel is a side tunnel that branches off of Level 40 of the Main Tunnel. It leads to the A-Tunnel and (later on) the N-Tunnel. The tunnel consists of thirteen levels which can be played with any character.

Suggested Characters: RunnerFront.png LizardFront.png ChildFront.png


The B-Tunnel consists of many levels with different colors, and different requirements to pass each level, so you may have to change characters regularly. The first few levels are mean't to be a Lizard tutorial, the middle levels are best with the Skater, and the last few are best with the Runner.

In the Bridge Building minigame, the Runner, Skater, and Student store all of their collected ringed boxes in Level B-13.


There are five (six if a certain secret is counted) cutscenes featured in this tunnel. More information can be found on the Story page.

Heavy Sleeper

After beating Level 40, a rather unique cutscene will begin. The Skater has just finished Level 40, and runs into the sleeping Lizard. He starts to apologize to the Lizard, saying he was caught off guard when the gravity changed. Then he realizes that the Lizard is fast asleep, and moves on.


After beating Level B-13, a cutscene will begin in Level B-12 featuring the Child and the Student. The Child asks the Student why she doesn't have a lab coat although she's a scientist. She says she doesn't need one, and starting to talk about what science is. He soon says that school science is boring and the Student begins arguing that science doesn't have to be boring.


There are 2 achievements exclusive to this tunnel.

Just Being Thorough

Suggested Characters: RunnerFront.png LizardFront.png

Dislodge all the crumbling tiles in Level B-3.

Straight to the End

Suggested Characters: SkaterFront.png ChildFront.png PastafarianFront.png

Beat Level B-13 without changing gravity.


Very easy
Not too easy
Almost medium
Over medium
Above medium
Fairly hard
Extra hard
Insanely hard

Difficulty of the Levels of the B-Tunnel

1 4 1 1 5 1


  • This Tunnel was most likely discovered by The Lizard.
  • At Level B-10 & after, you can start to see the Wormhole