Here you can play a lot of custom test chambers with the Portal 2 Mod "Thinking With Time Machine". The difficulties changes between the levels, so the tests are not getting more and more difficult.
If you found any Bugs or Glitches, please write a comment, so I can remove it!

Have fun playing these maps :)
And don't forget: Time Machines Are Always Fun !

Here are the solutions to all testchambers:
https://www.youtube.com/watch?v=mG7GOAe_vtQ&list=PLwK5cEYZ_K2TJPJbE8FnifGtIjYNwD2C0
The testchambers were played blind by LB, except for testchamber 2.
Here is his YouTube Channel: https://www.youtube.com/user/LB725C