- "That look in his eyes... Reminded me of a kid that went crazy last week. He was just an engineer, but something in him snapped."
- —Nathan McNeill
Crazed colonists are ordinary people who went insane due to the effects of the Red Marker on Aegis 7. Crazed colonists are significantly more durable than normal humans. Some are fighting back even with multiple limbs dismembered. It was currently unknown how they managed to fight through the pain and shock of such serious injury, but it was possibly related to the Marker's influence - boosting adrenaline levels beyond normal human ability. Decapitation was the most effective way to take down crazed colonists. Some crazed colonists are equipped with some form of armor, notably Engineer, Miner and security RIGs while others only wore their normal work clothing. In Dead Space: Extraction, they attacked only with their fists to the point of dropping any weapons that they are carrying to do so.[note 1]
- "I have no doubt they are somehow linked to discovery of the marker, but the exact nature of that connection is still unknown. Almost 40 percent of the colonists are experiencing a form of dementia. The obvious symptoms are acute depression, insomnia and hallucination. Incidence of violence and even murder also indicate extreme paranoia."
- —Dr. Terrence Kyne
All of those who became affected by the Marker showed similar psychological problems which could not be cured and only got worse with time. The first symptoms appeared to be: Difficulty sleeping, nausea and mild paranoia. They could sometimes be treated with over-the-counter sedatives as it was seen with Brant Harris and Vera Cortez, but this treatment remained highly ineffective. These symptoms did not interfere with the victims' perception of reality and allowed them to function for the most part, normally. However, within a short time, most afflicted personnel began to suffer from mood swings and a general decrease in self-preservation. Also notable are visual and audio hallucinations with increasing frequency. This stage was very short and typically lasted less than one day as it was seen with Natalia Deshyanov. Final stage colonists appeared to be immersed in total delusion or complete despair which are acting on their hallucinations in either suicidal or homicidal ways.
- Crazed colonists first appeared in Dead Space (Comics), but are not encountered as in-game enemies until Extraction.
- Crazed colonists are susceptible to decapitation which resulted in an instant-kill.
- Crazed colonists acted, attacked and sounded like zombies. This was seen in Chapter 2 in the office that had the exit outside. A woman was mauling a corpse and ran.
- In Dead Space: Ignition, Armado Creeg, an engineer and resident of the Sprawl possibly became one of the crazed colonists.
Notable Afflicted IndividualsEdit
- Albert Rutterschmidt 
- Brant Harris
- Hans Leggio
- Mario Lemus 
- Natalia Deshyanov
- Pete Fancher
- Ruben Villa 
- Sam Caldwell
- Vera Cortez
On The USG IshimuraEdit
- Blind Woman
- Challus Mercer
- Insane Nurse
- Unitologist Woman
- Isaac Clarke
On The USG O'Bannon Edit
- ↑ It is important to remember, however, that numerous colonists who lost it prior to planet crack did use weapons when attacking others.