Awesome info - that explains alot of what I've seen.
We will try to get it going by this weekend I think
I primarily wanted to know what to expect of the event once it is 'triggered' so I know it is working right.
I think what we have seen in the past must have been the bug - that the UN-attackable summoners would sometimes aggro us as we did all in our power to aggro them - sometimes merely standing next to them long enough

is all that did it - but now we know that in order for us to be SUPPOSED to attack them we needed to kill a ghost.
Now, again - I haven't been on my guy to look at the log since starting this thread cos of damned RL but I really don't recall a clue as to how to start this thing. Was the ghost clue or some other such included in the quest description but ppl like me didn't 'get it'?