Simmons(Deca)

In the time before the Renascence Cascade, before GLAdos killed 'all' of Aprature, Aprature developed the Portal Device. This back in when they were relatively new to the field, and was their major break-through. Though this device was rather cumbersome and could only do very little due to the technology of the time.
As the years and the technology progressed, the device shrank in size and wight, but grew in possibilities.
By the late 1980's they had managed to get the device to roughly the size of a standard rifle, and dubbed it as the 'Portal Gun'. The science team were contempt with this and expected a lot of data to be collected, until it was stolen.
With this Portal Gun's fate unknown, and with the development of their newest Portal device underway, the scientist only hoped that it would never land in the wrong hands, much less War.
You are a simple human solder during the Seven Hour War, who was presumed dead after being sent on a mission behind enemy lines. You have stumbled upon this device while just trying to survive. You ARE NOT humanity's last hope, you are simply just trying to survive.