Berg studied chemistry and took a particular interest in psychoactive medication. He eventually became an intelligence operative for Mossad, specializing in chemical interrogations, where he earned a reputation for being clean, efficient, reliable and able to make anyone crack. His methods were hardly ethical, but nevertheless non-violent, and Berg considered his services a "lesser evil".
Slowly, however, he began expanding his repertoire, dabbling in drug induced hypnosis, memory wipes and subliminal mind control. This became too controversial for the Mossad leaders who forced Berg into an early retirement. In 2015, he sold his property in Tel Aviv to, allegedly, travel the world. He has not been seen since.A polite and soft-spoken gentleman, Berg considers himself a humanitarian who performs necessary duties with the least amount to cruelty and indignity. He is nevertheless willing and able to inflict intense psychological terror and can be recognized by his trademark featureless silicone mask, which he uses to unnerve and terrify his sedated subjects.
- When killed or subdued, Berg drops a Lethal Poison Pill Jar.
- A cropped version of Berg's HITMAN™ target photo was reused in HITMAN™ 2.
- Berg's mask may be a reference to Michael Myers from the Halloween franchise, who wears a near-identical mask.
- Berg's mask may also be a reference to real life serial killer Edward Paisnel aka "the Beast of Jersey", who wore a similar mask in real life while he committed his crimes.
- Berg objects to some of Sean Rose's more brutal tactics. He talks with Penelope Graves about Rose's plans to kidnap some children in Shanghai and make something innocent kill them, (presumably, this is some Providence-related action.) Berg's dialogue makes it clear that he disapproves.
- Many militia members seem to think that Berg is strange or dangerous because of his mask, but in fact he is one of the more well-behaved members of the camp. He does not physically harm or verbally abuse his prisoner, he is polite to his co-workers and he entertains questions from inquisitive subordinates.
- If the prisoner Berg is keeping an eye on is killed, he will immediately run to a swingset at the back of the farmhouse and sit there for the rest of the mission.
- 47 could originally disguise as Berg, though this ability was cut in development. An image of 47 wearing Berg's outfit can be found in the game files.
- Interestingly, Berg's facial model is incomplete if seen without his mask, as he is missing his nose. This suggests that the ability to disguise as him was cut early in development.