A new mission was added on July 15, 2011 with dark falz 2 as the boss on any mission level, meaning you can do a C run at level 1 and get the chievo. Yay!
Name - Distant Memory
Location - Falz Memoria
Level Req - 1!
For more info check out this link:http://psupedia.info/Distant_Memory
If you need help with this or any of the other online PSU chievos feel free to send me a message on xbl. GT: FrogInTheStreet
Edit (6/10/12) - The servers are shutting down September 6, 2012, so this, along with the 4 other online achievements, will no longer be available when that day comes. Since the servers are shutting down, I decided not to renew my guardians license this summer as I planned, so I can't offer any help with the achievements anymore. However, if you have any questions, feel free to send me a message here or on XBL.
If you are looking to get the online achievements before the server shuts down, I recommend going to universe 1 or 2 on the 4th floor and asking around for help. There are plenty of nice people who play this game, so you shouldn't have trouble getting the help you need. Again, if you have any questions, feel free to send me a message.