I have recently discovered a way to get Invincibility on multi player the way to get it is. first you must pick a level with portals and scorpian launchers and a friend that is kind enough to do this for you ok now first tell your friend to get a scorpian launcher and meet you at the portal than go to the portal you stand directely in front of the portal then have him take your energy out to about ten of fifteen then while standing directely in front of the portal have him shoot you into the portal with a scorpian launcher and your friend will get a kill every time you go through the portal and come out if he shoots you. you will have 0 energy for ever unless you get any health so dont get health. I recommend doing this on Tellaportastic level!