User blog comment:Gruntburner/Mass Effect 3 Achievements Revealed/@comment-4118072-20120204224838/@comment-138.217.134.168-20120205071714

I dont know why but one theory i have is Shepard undergoes a drug/indoctrination induced dream and fights Saren again. It may be an attempt to break the Commander's mind, as after all Saren said defeating the Reapers was hopeless and that hopelessness would be sinking in at this point for Shepard. Just one possiblity.