Originally, Avatar-class AI were made to act as assistants to the one they were modeled after. They were given more personality than most other AIs, being given personality imprints by their creators. There was a presence of both Generation 1 and the more advanced Generation 2 Avatar AIs. During the Forerunner-Flood War, they became foot soldiers who battled against Infection Flood forms until the mass-production of Combat Sentinels. Unfortunately, most of the Generation 1 Avatrs fell prey to the Gravemind's influence and were defected. The few Generation 2 Avatars fought to defend Forerunner civilians until they were able to escape from worlds under siege but were eventually defeated. Only a handful have managed to somehow survive the Forerunner-Flood War and put into standby mode.