The Last Fortress

When I was watching Doom Eternal yesterday, the ending is that the Dark Lord Of Hell is like a copy to the Doomguy. This was very strange but then this morning, as I thought about it, I was wondering if the REAL Hell was occupied by the same person as myself, one person, me, doing good, and one person, the Lord Of Hell, doing bad. Like a good/bad, light/dark, positive/negative. Then I immediately thought, because of the knowledge of the happenings of Hell, focusing on it, that I had to...