Test Chamber 8 - Course 2 - Mass and Velocity - Co-op Challenges | Portal 2 | Gamer Guides®
Portal 2 level editor can now build co-op levels
Portal 2 Gets 20 New Co-Op Levels With Community Mod Update
In Portal 2's CO-OP hub just before the DLC course's disassembler, there's this other monitor that asks you to select a course, however, to this day the only one you can select