It uses two nearly duplicate skills in Unstable Aura and Unstable Pulse, the latter lasting for a duration of 175 seconds and dealing damage to adjacent foes when it ends.
It is quite a pushover if you pull the two Flame Guardians that spawn with him and kill them first. This also has the effect of disabling the nearby Fire Traps.
Also note that, like many bigger bosses, the golem will go down extremely quickly to the Necromancer elite skill Spoil Victor.