Board Thread:Theories and Rumors/@comment-5336393-20190110151206/@comment-4013721-20190111003908

To me, it would make sense that the Overlord would just be the darker parts of the FSM given form. after all, the Oni has the power of Darkness so it would make sense that the FSM also had that power, given how the Oni side of him gave him and his sons a longer life than mortal beings.

This explenation would also have some interesting ramifications to the events of Season 2 and 3 with the Overlord's possession of Garmadon and later attempt at becoming the Golden Master.