User blog comment:MerlinNimueh/Series 5: confirmed facts/@comment-4690063-20111221164139/@comment-4650675-20111221171709

No, not facts, just speculations. Mordred is a bit young to bring Arthur's downfall. So another strong enemy has to reappear, since every season after season 2 has 2 enemies of camelot. (one within and one out of the castle walls) However I hope there aren't any more enemies WITHIN Camelot and the enemies outside of Camelot increase instead.