Expedition - One shots and unkillable mobs

Some Expeditions are impossible to complete, they constantly one shot you with some golden circles that are triggered so fast that it's near impossible to avoid. Some monsters that spawn in expedition are impossible to kill without them killing you first. What extreme gear do I need to handle this? Everything else in the same map died very easy, Im not even doing maxed out maps…These mobs have some special icons under there healt bars but i cannot hover over them to inspect what it is, maybe I need to get into melee range to kill them? But going into melee range makes be explode and die...whata fun experience this is...

While we do choose our mods to enhance these I do agree that expedition creates dumb strong monsters when the mods similar to poe1 would not be threatening hardly at all. Recomb isn't strong enough to justify these super mutant runics.