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 following is a brief description of the story in the B-Tunnel. More information on the story can be found here.
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.
|Not too easy|
Difficulty of the Levels of the B-Tunnel Edit