It shouldn't come as much of a surprise that Bethesda's highly anticipated sequel to DOOM (2016), DOOM Eternal has broken sales numbers for the entire DOOM series. The sequel has received near-universal acclaim for developer id Software's improvements to everything from combat to graphics and level design, taking what worked with the reboot and ramping it up to eleven. Boasting an impressive 15-hour campaign, DOOM Eternal's focus on storytelling was one the biggest highlights for the series, exploring the back story of the Doom Slayer, the source of the demon's power, and leading to an exciting final battle that ties to an ancient alien race.  Warning, there are MAJOR STORY SPOILERS ahead.

The Story of DOOM Eternal

The story of DOOM Eternal is set two years after the events of id Software's 2016 reboot DOOM, with players taking on the role of the iconic demon-killing series protagonist, the Doom Slayer. In the year 2151, in an attempt to resolve the Earth's energy crisis, Dr. Samuel Hayden and the corrupted Union Aerospace Corporation have allowed Hell's demonic forces to overrun Earth, killing an estimated 60% of the population and forcing all remaining survivors to flee the planet. After being teleported away in the previous game, the Doom Slayer returns to stop the demon invasion on Earth by putting an end to the three priests of Hell, Deags Nilox, Ranak, and Grav, and their leader Khan Maykr, who seeks to sacrifice Earth and humanity for her own survival.

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The Back Story of DOOM Eternal

Before controlling demons and trying to take over Earth, Khan Maykr and her Priests were leaders to a divine race known as the Maykr's which live in a technologically-advanced alien city called Urdak, located in its own dimension, separate from reality. The Maykr are worshipped by the Argenta, a warrior race that caught the attention of the Maykr for their combat prowess, spreading their word from world to world in exchange for technology and knowledge.

When Hell's forces mysteriously appear and attack the Argenta, the Priests capture and study the demons, discovering that an "essence" called Argent Energy is the source of their power, and they decide to use it for their own technology against the demons. Once the war is over, it's revealed that Argent Energy comes from sacrificing the souls of the dead and that the war only ended after Khan Maykr struck a deal with demons that allowed them to access any world they wanted in exchange for unlimited Argent Energy to power both societies indefinitely.

The Back Story of Doom Slayer

DOOM Eternal story also delves into the backstory of the Doom Slayer himself, revealed to actually be known as "Doomguy," and originally from Earth. Found badly injured in the Ancient City of Sentinel Prime, Doomguy was inducted by the Night Sentinels, a militaristic clan that protects the people of Argenta, and trained in their coliseum where he climbed through the ranks, becoming one of their most esteemed members. When the demons attacked Argent D'Nur, their forces completely overwhelmed the Argenta and the Night Sentinels. In an effort to end the war, a mysterious Maykr took Doomguy to the Divinity Machine, a device that used Argent Energy to bestow Doomguy with enhanced superhuman strength and speed, transforming him into the Doom Slayer.

The Ending Explained

The reason that Khan Maykr made a deal with the demons in the first place was for the survival of her own homeworld, Urdak, a realm that requires energy as powerful as Argent Energy to keep the Maykr alive and immortal. Urdak's original energy source mysteriously disappeared, believed to have been stolen by an unnamed Maykr known as the Seraphim, and potentially later used on Doomguy to become Doom Slayer. Fast forward, Doom Slayer traveled across a myriad of locations from Mars to Hell, New York City and more, killing each of the three Hell Priests, and arriving on Urdak to confront Khan Maykr, but not before she began the resurrection of an unstoppable world-eating demon, the Icon of Sin.

In an attempt to stop the resurrection ceremony, the Doom Slayer stabs the Icon on Sin through the heart, instead awakening the demon from its dormant state, and allowing it to leave the realm and teleport to Earth. The Doom Slayer makes his way through Urdak fighting off Hell's demons which are now invading the homeworld and kills Khan Maykr before teleporting to Earth. In the game's final battle, the Doom Slayer fights and kills the Icon of Sin by stabbing it through the head with a Crucible blade, stopping the demon's invasion on Earth, and putting an end to the Maykr.

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Once the Icon of Sin is killed, a voice can be heard in the background as Doom Slayer walks away from the battle. "And you will be their savior," says the Argenta's King Novik. "Your strength will be their shield and your will... their sword. You remain unbroken, for your fight is eternal." King Novik is indicating that Doom Slayer is more than just a soldier, that he's a protector and guardian for humanity against the demons of Hell and any other threat that comes their way. In the final cutscene, a demon is seen playing with a Doom Slayer and Demon toy, only for the Doom Slayer to appear behind him wielding a combat shotgun.

DOOM Eternal offers an exciting campaign mode that expands the gameplay and lore of its predecessor, as well as a brand new 2v1 multiplayer experience called Battle Mode where players can play as a variety of demons, complete with their own weapons and play styles. In our DOOM Eternal review, we said: "From its action-packed opening mission to its blood-soaked final boss fight, id Software's Doom Eternal is a non-stop thrill ride."

DOOM Eternal is available now for PC, PS4, Switch, and Xbox One.

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