lord what the lord!
Interesting... could be done on BLAM!-G1 on SP, definately not MP though.
Current Biped, Vehicle, Weapon, level and asset modeler/animator/rigger/UV artist and scripter of NMT
I am just going to focus on creating a level.
Single player no xD
You will need 70 developers to make SP.
All you need is multiple BSPs and a speed detection script that switches BSPs to create the time travel effect.