The Doom Slayer continues his move through the citadel after he removed the head of that Bruiser Demon in that prison, took him a while but he killed it with the sword he stole from the Death Knight. He was walking up a tall stairway that reaches three floors up, holding that flaming sword on his right hand while holding his handgun on his left. He continued his onslaught against the demons, seeing that they are not slowing him down after what happen in that prison room.

At the top of the stairway lies a Summoner, creating some demons in front of it and sending them down there to slow him down, at the third stairway they collide against Doom. He kept firing his handgun at the Imps that came down to attack him, taking them out with one hit and those that got close to him will be sliced through by his sword. The Summoner will be force to retreat through the door when seeing Doom reaching the top, the Summoner appears inside this wide room, standing on a high ground and creating three Hell Knights to challenge Doom. The Hell Knights will jump down to attack him once they see him, seeing Doom shooting his handgun twice at one before switching to his sword to start clashing against them. Doom strikes down one of them then swings his sword to the right to hit against the other one, leaving a large cut on its chest and soon took a red energy blast through the face by his gun. The third Hell Knight claws his back and causing Doom to take a few steps forward before aiming his gun at it, only to fail when the Hell Knight hits his hand and losing his gun. Doom counters by swinging his sword and cutting through the face of the Hell Knight, he kicks its chest to send it collapsing and showing the head falling off before disintegrated.

The Summoner teleported near Doom when he looks around to find it before it creates more; he reverts to his grenade launcher to see if he could shoot it. The Summoner vanishes in three locations in the area before spawning another demon, creating a Cacodemon to let loose in the room. Doom spots the Summoner on time and fired his gun at it, damaging the Summoner but vanished yet again and appears nearby, floating behind Doom but was on lower ground. Doom notices the Cacodemon flying up to attack him, seeing he has no time fighting the Cacodemon right now, he charges to the Summoner but sacrificing his sword to kill the Cacodemon. He threw his sword towards the Cacodemon when it opens its mouth while running, sending the sword lodge inside the mouth to cancel its attack. Doom jumps down at the Summoner as it created three Imps in front of it but had no time to avoid this, seeing Doom coming from above; he punches hard across the face and sends the Summoner collapsing on the floor. Doom finally kills the Summoner by punching its face in yet again to remove the head, after that he turns to the Imps and starts ripping them a part with his bare hands.

Back outside, the UAC marines have pushed the enemy back after Team Wolverine appears on the left side of their position, fighting off against the demons and help push them back. There large exo-skeleton figure, Juggernaut was taking the lead but was walking slowly, aiming its two guns around but could only fire one at a time.

The Juggernaut stood in the middle of the squad as they stay on both sides as it walks slowly, soon stopping when seeing two Barons charging towards them. The marines took aim and open fire, avoiding the fireballs as the Barons get closer. The Juggernaut got a lock on them and uses the rockets that are still in stock, locking on one of the Barons and firing three of them straight at it, blasting the chest repeatedly and causing it to stop, soon realising that the Baron felt dizzy until finally its upper body split into pieces. The second Baron got close enough to leap into the air, landing in front of three of the marines as they move back, throwing a fireball at one of them and running at a one on its right, clawing his chest and sending him to the floor before throwing a fireball at him. The Baron throws another fireball but targets the Juggernaut, hitting its chest while it was shooting plasma rounds through the chest of the Baron. The rest of the marines surrounds the Baron and try to take it out before doing much damage, killing it right after it claws the Juggernaut through the chest, leaving a mark on the chest before it dies.

Stevenson was still alive and still with his marines as they continue advancing. He stops at a point when looking over to Wolverine's position, contacting them before moving forward. "Williams, you still there?"

William will be moving behind the Juggernaut to use him as a shield. "I'm still here…"

"We are in range of the fortress; we need to bring in the APC in position."

"Copy that. I will leave the Juggernaut to you." He looks back to his marines "You guys with me, come on!"

William and fifteen marines by his side retreats out of the warzone for now and make their way to the APC, there they will join Travis and the cyborgs on defending the APC as it moves. The vehicle will be driving through the rough road, making sure not to run over the marines while they are busy shooting at the demons. Travis will notice some help arriving as he is close of running out of ammo right now, hoping that they have some additional ammo so he could continue shooting.

"How much further!?" Travis calls to the marines when they arrive, asking if they know how far this APC has to go.

"Once the AC-31 flies out of the way, the APC will be in position to launch." William said

"And that there is the time we all run in the opposite direction right?"

"Pretty much."

"Sir…" One of the marines spoke to Travis, standing behind him and getting his attention "What happens if that guy is still inside the fortress while we fire the missile?"

"Well if he is still in there…. Let us hope that if he survives, he doesn't come back to kill us all."

Back inside the citadel, Doom continues his onslaught inside the citadel, he just took out two Death Knights by himself and stolen their two swords, igniting them in flames and continues moving, he was close of reaching to another room but suddenly stops when someone communicates with him. He was getting static for a while, soon hearing voices until he could finally hear someone. Doom was surprised at first, hearing the voice of VEGA in his helmet, contacting him just like old times.

"Marine… The UAC is planning to fire a nuclear strike on the location you are in; if you do not escape then you will surely die here. The UAC will fire that bomb inside the portal; try not to stay there longer."

Doom continued moving after he got that information from VEGA, soon to go through a prison room where the Cultist was waiting for him to arrive. The Cultist was standing in the middle with four soldiers standing behind it and four innocent people all on their knees, having their hands tied to their backs and clothes ripped apart.

"You are too late. Doom Slayer." The Cultist spoke in English to him, sending its voice through his mind "You could not save them; you cannot save all of them. They are all doomed to die in this destroyed world." The Cultist spreads arms out, showing it is unarmed "Just give up… It is too late to save this world. They are all going to die."

Doom held his ground while holding his two swords at the ready while the demons held their ground, not even thinking of attacking him but the Cultist will be the one to make the move. The Cultist let loose Hell's Energy through all four of the civilians, all four of them morphed and changed into Barons, huge Barons that screeches when they are complete.

Doom backs away while the Barons attack by throwing their fireballs at him. He got out of the doorway on time without taking any damage, drawing the demons out of there and moving to a wider room where he is right now, watching the Barons running in and chasing after him. He stood ready with his two flaming swords as he moves backwards into the room and watches the Barons. He thinks for a moment to figure out to see if he could take them all out at once or try to take them out one by one then make a run for it to avoid serious damage from the others. He plans to take them out at a time, knowing that if he attacks them all at the same time then they will surely kill him before he could take out the others.

Doom makes his move on running to his left and jumps up on a square shape high ground; he moves back and waits for one of them to jump up there, which would work as one of them jumps up here. He charges straight towards the one who got up here first, he boost jumps through the air and stabs both swords through the chest of the Baron, sending the two falling back down and crashing on the ground with him on top of the demon. The Baron dies instantly during the stabs, he then pulls the swords out and looks to the one nearby, taking two hits to the chest by their fireballs and sends him moving backwards. He backs away and still held onto his swords, noticing it now that they are no longer on fire anymore, seeing they must have been a limit until they ran out of power. The swords could only stay in flames for a time, only Death Knights and others who could use Hell's Energy could make them stay on permanently. This became a serious problem now because the swords are just regular looking swords, seeing they are blunt and could break anytime. He would have to ditch the swords and avoid the fireballs from the Barons.

Doom backs away and continues moving away, avoiding the Barons as they keep throwing fireballs at him, seeing that with no weapons or any power-ups right now, he can't do much to destroy the Barons. While he was backing away from them, seeing they are line up to grab him, something would get Doom's attention. When he looks to his left, he spots it, seeing a Berserker power-up right in the corner, floating there, begging to be use against the demons.

Doom did not hesitate when he made a run towards it while the Barons chase after him, running towards it and had to boost jump to reach the high ground on where the Berserker is. Once he grabs it, he unleashes the pure rage of his strength as the power-up consumes his body for a second in red energy. When Doom turns back, he lays a hard punch through the closest Baron that got closer to him, punching the leg of the Baron and removing a large chunk of it, causing the Baron to fall on one knee. Doom punches again and this time to the face, removing another chunk of the face and sending the Baron collapsing back.

Two more Barons remains right here and he quickly took care of them, punching one of them and doing the same thing before. The last Baron became a problem because it grabbed him, lifting him up and slamming him against the wall. Doom will finish this by grabbing the bottom jaw and the top jaw with his hands, using his strength; he rips the top head right off then kicks the chest to send it collapsing onto the floor with him standing on top of it.

Doom returns to the Cultist with what is left of his strength, the four soldiers are all what is left of protecting the Cultist. The soldiers will move to the door to see if Doom is dead, only to fail when he arrives through the door and attacks them, charging towards two of them and grabbing their faces, slamming them to the ground then crushes their heads in. The other two demons move back while firing at him, unable to slow him down as he rips them apart while the Cultist watches, unable to turn them into Bruiser Demons on time. With them dead, Doom walks in front of the Cultist who still stays in the bubble shield.

"You cannot save them all, Doom Slayer." The Cultist spoke yet again through his mind "You cannot save this world!"

Doom punches one more time with what is left of his power, punching through the shield then pulls his arm out, causing the shield to break afterwards. He ran out of power after that but that did not stop him, the Cultist was defenceless against him and he simply grabs the Cultist and throws it to the ground behind him. He ends this by walking to the side of the Cultist, laying his boot down at it and crushing the head completely.

Meanwhile, outside the demon fortress, the UAC has been taking some serious casualties on their side when Mancubus' got into formation and let loose their huge fireballs upon the field, sending many marines flying in the air while some torn apart. There are several Mancubus' seen on the field, four of them are on the ground while two of them are on the walls, getting their sights upon the marines as they were close. The marines got close enough to get closer to the walls, seeing the demons are unleashing heavy bombardment to the marines.

The aircraft was moving sideways to avoid heavy shots from the enemy, seeing that if they continue where they were before then the Mancubus' would surely shoot them down, they will move to the side and target the demons on the wall. The co-pilot was checking out on the screen in front of him, seeing a handful of demons coming over the walls to attack the marines, the pilot decides to focus their fire on the walls to give the marine's some time. The co-pilot was still checking on the screen, soon realise that there is gunfire happening down there, seeing demon weaponry firing against each other, coming from the citadel entrance.

"Hey are you seeing this?' The co-pilot asks while still watching the screen "Get a zoom in the citadel entrance."

"What the hell?" The pilot checks the screen, going for a zoom in and seeing human life signs down there at the entrance of the citadel "Holy shit…" He then contacts Stevenson "Stevenson, we got contact of human life signs inside the fortress."

Stevenson was against large rocks and trying to hear the pilots while gunfire is going off close by. "Can you repeat that? You have to speak louder!" He looks out the view when seeing two marines running over, firing their guns at the Mancubus' but did not last long. One of them lost his upper body by one of the shots while the other one lost a leg, seeing him collapsing onto the floor.

"I said we got people inside the citadel!" The pilot yells "We got people down there, they need some assistance."

"In case you forgotten, we don't have the strength to breach their walls… We are here to wipe out the fortress, not a search and rescue mission."

"So what the hell do we do?" The co-pilot asks

"We help them out as much as we can." The pilot said while targeting the two Mancubus' on the wall "Let's see if we can help both sides."

The aircraft open fire on the wall, targeting the Mancubus' on the wall and getting their attention, unable to use their missiles due to already using them and are close of running out of ammo soon. The aircraft flew closer while continue firing, trying not to hit the citizens as they held their ground inside the citadel. Several of them were carrying demon weapons to hold off against the other demons, the others who are still alive were behind them, crouching down while the defenders continue firing. One of them soon took a hit to the chest by one of the Imps, sending him to the ground and causing them to move back a bit, soon realising the aircraft was moving closer towards them while firing more rounds down at the demons.

"Help at last!" One of them said while running out of the doorway and waving his hands out to them

"Wait!" One of them shouts to him while getting up to run at him but stops when he took a hit by the aircraft's weapons fire. "…"

"Get down!" The other one grabs him and pulls him back, making sure they do not lose another one from friendly fire "Wait for them to land."

The aircraft continued firing while moving closer; killing one of the Mancubus', the other one exploded by one of the marines who was carrying a Gauss Cannon with him to the battlefield, taking out that Mancubus with one shot. After the aircraft ran out of ammo, there was no time to waste. The aircraft hovered closer to the wall when turning around, having the back facing the citadel and opening up the bottom hatch. The moment they saw the hatch open the ones with the weapons moves out of hiding and cover the others as they try running towards the wall, climbing up there to try to get on board. The others keep firing at the demons and they try to get over there, soon to go bad when a Summoner appeared, letting loose this horizontal energy wave towards one of them who turn his back to the Summoner. The energy wave goes straight through his arm, splattering his blood over the place while the others watch, just when he turns towards them, a Hell Knight came from behind and rips him in half, splattering his blood over the Hell Knight while it screeches.

"We got to go!" One of them shouts while running towards the wall

While they make a run for it while the Hell Knight chases after them, something suddenly came out of the citadel by jumping out one of the windows. It fell all the way down and crashing hard onto the ground, landing right in front of the entrance of the citadel. Of all the people who could have survived a fall like that, it had to be of course the Doom Slayer as he lands there on one knee, having his fist hitting the ground but he rose up and getting everyone's attention.

"Who the hell is that guy?" One of them said when looking towards him. He looks back to the Hell Knight and seeing it charges towards him and not them.

Doom charges towards the Hell Knight then boost jumps forward to get a fast leap at the Hell Knight, punching its face and sending it to the ground, allowing him to get on top of it and starts punching its face a few times before getting off. He took a hit to the back by an Imp, when he looks towards it the Imp runs away and regroups with the others that were nearby, seeing fifty demons all standing there and was ready to attack him but they held their ground. Doom was tempted to go and kill them all however, he decides to make a run to the aircraft before it takes off. He turns back and makes a run towards it while it slowly moves away from the wall, he boost jumps on the wall then again when he got to the edge, jumping upwards and grabbing the bottom of the aircraft with both hands.

"Were clear." The co-pilot said when turning to the left to look out at the window

"Come on, give him a hand." One of the people said when crouching down to help Doom get inside

Two more people came over to help him get inside, seeing he is slightly heavy than they thought "Damn this guy is freaking heavy!"

"Stevenson this is AC-31. We have precious cargo and we are out of ammo, you marines are on your own. We are returning to Firebase Bravo."

"Copy that. We are preparing to fire the missile." Stevenson said to the pilot then contacts Travis "Sergeant Travis, is the APC in position?"

"Just give us a minute!" Travis responds while crouching down the APC while the others were around it, shooting at the demons while it keeps moving forward. Travis would take out the super shotgun and walks over to the others, aiming his super shotgun at a Cacodemon and blasting that to bits.

The APC was getting closer to position once the demon threat was no more and the demons stopped attacking them, luckily for them they could finally breathe normally. Everyone around the APC began moving back, moving back to the APC as it moves, moving closer to the hill where it needs to lock on target. The scientists will have to use one of the satellites to link with the missile, using their iPad; they use the view of the satellite to get a view of the portal where they will place a lock in target for the missile to go. After that, the missile began to rise up as it goes moving at the back of the APC but sticks up in the air, getting it ready to fire the missile and wipe out the fortress.

Travis will come opening up the hatch when he was crouching on top of the APC, looking down at the scientists as they look back at him. "What's going on?"

"The rocket is prepped and ready to launch."

"About damn time… Are we out of the blast radius?"

"Yes but everyone else isn't…"

Travis sighs then looks back, looking towards the battlefield as he could still see gunfire going off. Travis will go and contact Stevenson on the radio. "Major Stevenson can you read me? Major Stevenson please respond, now."

Stevenson was still in a firefight and could only hear Travis a little bit as if he was whispering to Stevenson. He was busy right now as he was shooting at the demons in front of him, taking out two Imps then shoots at the Mancubus, quickly going back into cover when it fired back at him. He looks out at his marine's as many of them lie dead while some were holding position, going into cover and trying to shoot at the demons. Stevenson soon looks over at the Juggernaut as it is taking serious damage to the demons, seeing they are now targeting the Juggernaut. The Juggernaut would take two hits to both arms by two fireballs from a Mancubus, seeing one of the arms falling off his body, seeing the Juggernaut leans its upper body forward as if it was about to collapse but it ends up collapsing backwards onto the ground.

"God damnit…" Stevenson mumbles

"Major Stevenson, this is Sergeant Travis." Travis said on the radio "The missile is ready, I repeat, the missile is ready. You got to get the hell out of there before we could fire."

Stevenson finally answers to Travis "This is Major Stevenson. Fire immediately, we don't have much time left."

"Sir I can get back out there, help you out an –"

"There is no time!" Stevenson turns his head to the side when seeing a Baron next to him.

The Baron turns towards him and screeches at him while Stevenson starts shooting at it, only to do little damage to it before the Baron takes him out with a fireball to the chest. The Baron turns to the other marines and throws a fireball towards one of them; it would then take a leap in the air and slams on top of that marine before it throws another fireball at someone else.

Stevenson was still alive but barely as the fireball did not go deep enough to kill him. With his last breath, he contacts Travis once more to make sure that he got it clear. "You have… Your orders… Get it done, soldier."

Sergeant Travis took off his helmet when looking out at the battlefield from where he is, seeing the gunfire and explosions going off from where the team is, seeing they are not doing any good out there now as the demons got the advantage. Travis will look back to his marines then to the cyborgs, seeing them looking towards him while he looks back at them, seeing it is up to him to decide what happens next.

Travis hesitated for the moment but when he looks at the scientists, seeing them standing on the APC, he finally gives them the order. "Fire the missile."

"But sir –"

"We have our orders!" Travis said to the marine then looks back to the scientists "Now fire the fucking nuke."

Travis and the others around the APC begin moving back away just to avoid the smoke from the missile, the two scientists will join them as staying in the APC might not be a good idea. The one with the IPad was ready to begin the launch as requested, once they are, further away from the smoke, he looks down at the IPad and presses the launch button. All of them will look towards it when it lets loose into the sky, heading straight towards the fortress and hope that it does not blow up early.

"All forces, the missile is away." Travis radios everyone who could hear him in the area "I say again. The missile is away."

The missile did its job as the demons look up and watch as it goes straight towards the wormhole, heading straight through undamaged and not targeted by the demons. A minute later, it will do exactly what the missile is supposed to do, explode in the center of the portal that is between Earth and Hell. Igniting flames and Argent Energy, twisting this massive power into a huge explosion, destroying the connection and unleashing a terrible explosion on both sides. The entire demon fortress annihilated by the blast, the flames would go blasting through everything and incinerate all the demons and all humans. The blast was so huge that it sent everything flying into the air before being consume by the flames, seeing that the flames zoom through the walls and went straight for the marines, wiping them out with a blink of an eye.

Sergeant Travis and those who were with him watch in shock as the entire fortress that held many demons, wiped out with a blink of an eye. Doom and the others on the aircraft were unable to see it due to the hatch being at the bottom, unable to see the explosion. Very soon, the portal itself closed but it triggered a serious earthquake, as the portal became a sinkhole, sucking the whole area through to cover it up, leaving no trace of anything or anyone.

Sergeant Travis makes contact with Firebase Bravo once the whole area sank. "Firebase Bravo, this is Sergeant Travis… Operation: Tartarus is complete. I repeat, Operation: Tartarus is complete. We request a pickup."

"You think we made the right choice?" One of them said who stood next to Travis, still looking out at the view "Major Stevenson and the others…."

"He wanted us to do it." Travis said while placing his helmet back on "They knew what they were doing."

"You think they would have done the same thing if it was the other way around?" He asks when turning his head to Travis.

Travis would contact the AC-31 while looking out at the sinkhole "AC this is Sergeant Travis, operation is complete. Do you have an armoured marine on board?"

The co-pilot got out of his seat and went to check on everyone at the back, seeing all the survivors sitting down while Doom was standing there at the back, looking straight towards him. "Uhhh… I found him…"

Travis sighs relieved then looks down when raising the super shotgun as he still had it in his hands. "Tell him I got him a present, he's going to need it."