Gabriel is a lifelike robot. He was in love with Grace, but due to their nature as robots they had to keep their relationship secret. He is also responsible for the attack on Nicholas Monrova and his family.
After an attack on the Monrova family - that also killed Grace -, Nicholas stopped trusting everyone outside his family since the attack had to come from within Gnosis. He then resolved to remove the board members with the help of the Lifelike. Nicholas created a nanovirus, which he called Libertas. It was a program that erased the Three Laws in a lifelike’s core code. He infected Gabriel with it and had him kill every sitting board member except Silas Carpenter.
Gabriel himself still suffered from Grace's death and so he stole the nanovirus and infected his fellow Lifelike. Together they seized Babel's upper levels and captured - and ultimately killed - the Monrova family. Still, Ana survived with life-threatening injuries and was rescued by Ezekiel and Silas.
- Gabriel is modeled after Nicholas Monrova.