WMG / Chronicles of Harmony's End

At some point, Array will become a villain and the Elements of Harmony will be used against him.

Think about it, when Discord becomes sealed, it's possible that Array might decide to carry out his vision of a perfect world through absolute order unimpeded. But he will be foiled by the Mane Six and the Elements of Harmony, since the fragmented God's purpose is to ensure Balance Between Order and Chaos.