Based on the ohotmu
when Demogorge released all of his energy to revert back to Atum it pretty much created all the Godly energy that created all the current pantheons of gods, the skyfathers the earth related Demons and hell lords including mephisto (although mepshisto origin has been retconned)
http://img5.imageshack.us/img5/3981/annualthor10page6.jpg
just to show how powerful he is in just "Atum" form , the egyptions mistaked odin for a reincarnation of "Atum" and the gap from atum to demogorge is as big as the gap from banner to hulk as have been said
How is PC Darkseid going to beat someone who is supposed to be more powerful than all of earths magical dietys combine at his peak?