Gordon Freeman

Him being cool

Gordon Freeman (also known as Captain Gordon Freeman of the Intergalactic House of Pancakes) is a brilliant theoretical physicist and a soldier. He has killed Master Chief once but he did it for a publicity stunt. He defeated an entire race of Gordon aliens from the shame Full-Life. He then retired when he was 64 years old. He's actually the G-Man's brother.

Scientist

Gordon Freeman and Albert Einstein were separated at birth. He went to some website and found him as one of his relatives. He went to talk to him and he taught him physics then he abused it by killing stuff, eating stuff and blowing stuff up.

Soldier

He became a soldier when the Gordon aliens were disturbing his research. He killed many stupid Gordon scientists and Gordon himself. He only used a shotgun and a crowbar, but amazingly Chuck Norris gave him a “good job” star and one Infinity UnDollar bill, being the only Defeatable who has ever received one. 

Retirement

Mario was overtaking his shaming career so he decided to retire because he was so annoying. He then moved to the Aperture Science Lab where he met the idiots Glados and Wheatley. He sleeps in the cake room where at the end of the shame Not Portal you become fat because Glados gave you too much cake.