Not sure if this is intended or not but prior to the patch today if you engaged a spider in hoh it would only nuke whoever was on the hate list, today they just ae everyone and it seems to be a bit more frequent.
The ae range is pretty big, if I am in the middle of the courtyard and the other group members are at the top of the stairs they still get hit unless they go all the way to the back wall.
Maybe this is how they are supposed to be, just pointing it out since this was not how they were prior to the patch.