That same year he was made consul posterior, serving alongside the emperor.
He accompanied the emperor to the Battle of the Margus River, but ended up betraying Carinus and possibly even killing him on the battlefield, turning the tide of battle in favour of Carinus’ opponent, Diocletian.
[2] With the death of Carinus, the new emperor Diocletian rewarded Aristobulus by retaining him both as consul and as praetorian prefect for the remainder of the year.
During his time as governor, Aristobulus undertook major building activities.
His tenure as governor probably ended on 1 July 294, when he was replaced by Cassius Dio.