Who is the DOOM Slayer?

The 1st Testament

The 2nd Testament

The 3rd Testament

The 4th Testament

The 5th Testament

The 6th Testament

The 7th Testament

Timeline of the story

The timeline is as follows:

The Seraphim Quote

Olivia Pierce Quote

In the end

There have been many speculations on his identity. All we know clearly that he wore the "Crown of the Night Sentinels" and was their leader. Is he a demon? An angel? Or just an Argent D'Nur citizen? More specifically, is he the Betrayer or not? Let's examine the scriptures and testaments closely and try to find clues.Let's start by examining the Slayer's Testaments, which were clearly written after they managed to defeat him."In the First age, in the first battle, when the shadows first lengthened,..."This line is clearly talking about the battle of Argent D'Nur, as it was in the First age, and it's when the shadows, or Hell forces, prevailed "lengthened"."... one stood. Burned by the embers of Armageddon, his soul blistered by fires of Hell and tainted beyond ascension, he chose the path of perpetual torment. In his ravenous hatred, he found no peace; and with boiling blood, scoured the Umbral Plains seeking vengeance against the dark lords who had wronged him."Burned by the embers of the first battle, apparently he chose to stay for revenge.His soul, tainted beyond ascension: I believe beyond ascension to heaven, or redemption. Thus, he will never find peace. He did something really wrong, and can't atone for what he's done, and won't be forgiven and ascend to heaven any time soon.He sought revenge against the dark lords, who had "Wronged" him. So apparently he was wronged by the dark lords somehow, and wants vengeance and redemption.So this means that the DOOM Slayer was wrong by the dark lords, and decided to stay for revenge.Again, the testament mentions that he sought "Retribution".I don't understand what the divide is or what is meant by it, but it seems like no demon has done what he did with it.The seraphim bestowed upon him terrible power and speed. The seraphim is supposed to be actually an angel. So this means that when an angel found that he chose the path of redemption, he thought of giving him more power to aid him in his quest.And apparently he broke the obsidian pillars of the Blood Temple in the Kadingir Sanctum.Apparently he spend doing this for "eons". Meaning for centuries, hundreds of them.We know from this testament that a "Titan" has rose to power and challenged the DOOM Slayer.This probably happened in the 3rd age. Meaning that this maniac spent 2 ages in hell, probably for millennia, just tearing apart demons.In the Cyberdemon data, it is revealed that when the expeditions started to go to the Titan Realm, they found a "Baalgar Demon" remains. they collected it and Engineered it with Argent energy to give the Cyberdemon.They also mention that the Corrax tablets found, mentioned an ancient battle in the Third age. That's probably when the Titan fought the DOOM Slayer after "eons".Someone betrayed the dark lords and gave the DOOM Slayer his armor, forged by Hell. That's why his suit has that symbol on the helmet, as it was forged in Hell, not by the people of argent D'Nur.We know here that the DOOM Slayer fell, by collapsing the temple over him.When we put all these together, to me, it's very clear that the DOOM Slayer is actually the Betrayer.In the 1st Age, Hell constantly wants to take over the Argent City, to harness the energy and expand their dominion.The Slayer is the crowned leader of the Night Sentinels.He loses his son during the back and forth battles.He wants him back.He betrays the Sentinels, and the city, by guiding Deag Grav to the Wraiths.The Hell priests put a curse on the wraiths, to at last, siphon their energy.His son is returned to him as the Icon of Sin.The Icon of Sin tears the Argent City apart while everyone watched helplessly.Wronged, consumed with rage, seeking vengeance, retribution, and redemption, the Slayer decides to take revenge on Hell.An angel decides to help him by giving him immense power.A demon decides to help him, forging an armor for him.He spends eons battling in Hell, choosing the path of perpetual torment.He defeats a Titan in the 3rd Age.He is ambushed in the Kadingir Sanctum, and stays in it entrapped in the tomb for almost an age, until Samuel Hayden revives him.Have you ever noticed right when the game starts, what happens?You see the Slayer mark being drawn with blood slowly on the screen, then someone speaks saying the following:I have not one inch of a doubt that this is the Seraphim speaking, specifically the moment he gave him his power.He made him way worse than Demons, till he finishes it, and destroys Hell!Have you ever noticed what does Olivia Pierce tell you when you see her the first time in the Foundry?She says:The first time i played the game, when i had no idea or understanding of the story, the moment she said that, it instantly occurred to me that she is talking about the protagonist's loved ones. It seemed odd if she was talking about the UAC personnel. No.She was talking about his past. She was talking about the Night sentinels, his son, the Argent City. The way this sentence is said, the tone of voice, the words used, only signifies this meaning.I am really convinced that this is the story and this is how it went on. My mind is very much locked on the idea that the Slayer is the Betrayer.We also have to notice that the Ungmar Codex, where the character is called the Betrayer, was written centuries before the Slayer Testaments, where he is called the Slayer. So things change. And the tides turned, and how Hell views him now is different.