I have noticed that the demons in the new HEs have a tendency to agro to and follow players transitioning through the event on the way to other areas on the map. This then blocks new mobs from spawning until the wayward ones are hunted down and destroyed or drop agro and return. While this can be helpful in some HEs (letting the Harpers gain strength) it can cause others to fail (defeat incoming demons). Ultimately this can be used to grief players trying to complete HEs for campaign currencies in some cases and give a guaranteed win in others. The demons should not be able to leave the HE area. We see a lot of this in the Arsenal in the Dread Ring, and it is extremely frustrating.
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