|Part of the Jonson family|
|In a relationship with Caroline|
|Biological children: Chell (via artificial insemination)|
Ratman used to be a student of Portal High School during the era of TEEN FORTRESS 2. Notably, his real testicles were exploded in an incident, and therefore he had to replace them with the Space Core and the Rick Core; as he puts it, "I'VE GOT BALLS OF STEEL!". He also assisted Gabe Jonson in building GLaDOS; however, due to a mishap, his DNA was sampled while "test toob babies" of Gabe and GLaDOS were made, and therefore, he is actually Chell's biological father.
During the era of ITS MY LIFE!, he is seen fighting bad robots, including GLaDOS and CHELLGADOS, in Portal Labs, and thus gladly assists Marrissa Roberts. However, CHELLGADOS shoots a portal to the moon, throwing Ratman into space. While Marrissa originally believed him to be dead, it was later revealed that Space Core can breathe in space, allowing Ratman to survive.
Thus, Ratman appears, alive and well, during the era of THE MARRISSA GAMES. As he tells, an asteroid hit him and he went back to Portal Labs, where he starts a resistance against President Snow's rule. He converts Portal Labs into a floating facility and leads it to where The Capitol is. He is killed by GLaDOS's "nerotoksin", but is resurrected by Wheatly's life-bringing spell. He thus takes on Portal Labs and uses it as his secret police.
- ITS MY LIFE! (First appearance)
- TEEN FORTRESS 2
- Portal: The 4th Millennium: The Trollfic Edition
- THE MARRISSA GAMES