Warning: Spoilers, spoilers, and more spoilers! Ordinarily, this warning comes at the end of the introductory paragraph, but in an article about Doom Eternal's Samuel Hayden, his very identity is a spoiler. Without him, there is no Doom Eternal, there isn't even a Doom franchise. As a background presence throughout the series, he's managed to work up to a leading role starting with Doom (2016) and his legacy has only become more potent after The Ancient Gods: Part 1.

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With a history going back to the dawn of humanity, it's no wonder that this cyborg has a role to play in the battle between heaven and hell. His story isn't contradictory, necessarily, but it is confusing to mortal minds, even genius mortal minds. As of this moment in the Doom universe, here's what we know about Samuel Hayden.

10 How Many Other Aliases?

Doom Eternal Samuel Hayden Head Models

Gamers can be forgiven for calling Samuel Hayden "Ol' What's His Name." The guy has a list of aliases that might be, quite literally, eternal. Based on codex entries and in-game experiences, Samuel Hayden is also the Seraphim, Hooded Figure, Samur Makyr, Heretic, and the Defiler.

There are a bunch of things that make no sense about Doom Eternal, but the aliases are understandable for a guy that doesn't exactly want to announce his multiple roles. It's clear that the characters only get a single lifespan to figure out who he's been, but they'll have to wonder how many other people he could be.

9 How Much Of The Resume Is Fake?

Doom Eternal Samuel Hayden Follow To Office

Samuel Hayden lied on his resume. Not just a little; a lot. To be fair, it's hard to imagine employers would look at "administrator to The Father since the creation of the world," and think, "Yeah, this guy sounds like a quality scientist."

He made up a family to be born into and claims he was an intellectual and philanthropist with great contributions in the fields of thermodynamics, electromagnetic theory, and nuclear sciences. He also said he established his own institute to help young minds. Exactly how much of that is true yet another Doom Eternal unsolved mystery.

8 What Kind Of Relationship With The Father?

Doom Eternal The Ancient Gods Statues Of Gods

As more games and downloadable content come out, players are learning more and more about what happens behind the scenes of the Doom franchise. It's now known that Samuel Hayden had a relationship with The Father.

The first inquiry that comes to mind regards the genetic relationship. Is Hayden The Father's son? The other questions involve the state of that relationship. Hayden believed in destroying Davoth and Hell along with him, but The Father disagreed. Was this a violent disagreement? Are they estranged?

7 Why Serve And Betray Khan Makyr?

Doom Eternal Khan Makyr Pointing

Despite a few details that it seems every player missed in Doom Eternal, no amount of codex hunting is going to yield answers about why Hayden ever served Khan Makyr. Did Hayden, at one time, agree with him, or was the plan to betray him all along?

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It is acknowledged that Khan Makyr is a villain of the highest order, but one can't help but wonder if Hayden bears some of that responsibility. It is implied that Hell was created because the betrayal forced the Khan Makyr to feed off of these minions or die. It's unknown if Samuel Hayden knew that would happen.

6 Was The Cancer Ever Real?

Doom 2016 Samuel Hayden Badge On Wall

Gamers might have a few tips and tricks to surviving the harsh reality of nightmare difficulty, but surviving stage IV brain cancer? That's another matter entirely. It is explained that Hayden transferred his brain into a robotic shell in light of just that.

The transfer included his frontal and temporal lobes and cut out the rest, but doing so would have made Hayden a completely different person with a new personality, which did not happen. It's later revealed that he made the change in order to invade Hell as a cyborg since he couldn't do so as a human. So was the cancer ever real?

5 Can He Transfer Consciousness Into Anything?

Doom Eternal The Ancient Gods Samuel Hayden As Seraphim

Players are learning every day about sweet new things they can do in Doom Eternal. One of those nifty tricks is that the Slayer can use stations to transfer his consciousness into a Revenant temporarily. But he can't do so permanently, at least, not yet.

Conversely, Hayden has had multiple different bodies and spheres that have housed his identity. But he is occasionally trapped in his bodies from time to time. So if this power is not based on will, is it a spell or a technology? How does it work?

4 Will The Divinity Machine Be Used Again?

Doom Eternal The Ancient Gods Seraphim And The Divinity Machine

While hunting for secrets, players have been keeping their eyes out for the somewhat appropriately named Divinity Machine. To explain the disconnect between the original games and their modern counterparts, fans learn that the Slayer has been enhanced with Hayden's invention.

So why hasn't it been used to make a thousand Slayers? Could it only be used once or is there a very rare battery for it? The existence of such a machine is something Hayden keeps to himself and players rightfully have to wonder if it can be, or has been, used again.

3 Why The Change Of Heart?

Doom Eternal Samuel Hayden Torso And Head

The initial reason for Hayden's label as the Heretic, which is given to him by two separate groups for different occasions, is that he insisted to The Father that Hell must be destroyed and The Father disagreed, which led to him being cast out and his sole responsibility for the current realm of creation.

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But at the end of The Ancient Gods: Part 1, Hayden does to the Slayer exactly what The Father did to him; he tries to stop the Doomguy from finishing off Hell's leadership. Has Hayden seen the wisdom of The Father or is there something particular to the timing that might result in disaster?

2 Why Choose The Slayer?

Doom Eternal Art Doomguy With Crucible

During Doom (2016), players are constantly butting heads with Hayden, to the point of wondering if he is the secret antagonist based on his interference with the Slayer's objectives or the sneaky protagonist based on saving the Doom Marine and imbuing him with great powers.

According to multiple data entries, Hayden saw the Slayer's military training and was impressed, enough to rescue the Doom Marine in an expedition and empower him. But if the Divinity Machine can make anyone powerful, wouldn't it have made sense to get to know some more possible candidates and select an individual with the most similar mentality?

1 Is He Starting Another War?

Doom Eternal The Ancient Gods Samuel Hayden With Crucible

The latest installment (The Ancient Gods: Part 1 at the time of this writing) shows the entity known as Samuel Hayden being saved by The Father, who pulls him out before the Slayer can do any lasting damage to him.

Is this a disagreement that Hayden is ready to let go of? Will he join The Father and abandon the realm? Or will he so strongly change his mind to believing that Hell should not be destroyed forever that he will fight the Doomguy as he continues his demon-killing rampage?

NEXT: 10 Hardest Enemies In Doom Eternal