Strange Behavior of Amon in Syrcus Tower

Hi, last night I ran Syrcus Tower for the 1st time but on the next to last boss, Amon, others were saying it was acting funny. They'd explained the fight in the beginning but Amon did none of the things they had described. There were no adds and I don't think it used any abilities. The fight was very easy and people were saying it was bugged but I'm not sure because I never did the raid before.

During my first time running it, someone from the alliance informed us that this bug may happen, but I believe that the encounter went as it was planned. I have heard about that bug, but haven't witnessed it.