Observer Totem increases Alert Level when you are close to them. It requires the Perception Job.
One of the core issues is that it isn’t necessarily obvious when you are approaching these totems or when you are in range of their Alert Level aura. GGG will be improving their visibility in a future update (both where they are and indicating when your Rogue specialising in Perception has made them vulnerable to damage).
Currently when a totem uses its Alert Level generation skill on you, your Alert Level goes up unless you kill it before it finishes using the skill. GGG will be changing it so that the skill essentially travels out in a wave that you can run away from or avoid. It will only increase the Alert Level if you are hit by it.
Buy PoE Currency Cheap