Disclaimer: I don't own RWBY which is owned by Rooster Teeth. I also don't own Doom which is owned by ID Software.

Salem is in Evernight Castle at the Light of Darkness. Talking to some voice from a Seer.

"So, they have all fallen, I see," Salem said.

"They have," the unknown voice said.

"A shame that she never got to meet him. He would've been the perfect pawn for her," Salem said. As she thought of one who once made a deal to preserve herself and the bloodthirsty beast.

"He is, indeed," the voice said through the Seer.

"So, what should be our next course of action?" Salem asked.

"He knows of our deal. The Usurper's envoy told him everything about us. It is time for Remnant to know the true meaning of destruction. The Relics will meet before he can lay his hands on any of them. And I will have your enemy's soul in my hands," the voice said.

"Of course," Salem said. Thinking of how she may finally be rid of Ozpin.

"And as for the one you have who seeks power, I have my interests in her. I look forward to watching her burn everything the two of them have made," the voice said.

"Well, she does interest me as well. Now to see if Remnant can survive…it's oncoming destruction…" Salem said.

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-Mountain Glenn-

It has been entirely overrun by Grimm. It seemed like they pretty much owned the place, now. Well, they OWNED the place, for now.

Then the Doom Slayer came through a portal. He was wearing his Upgraded Praetor Suit.

All the Grimm turned to him. They could FEEL his anger and rage.

The Grimm rushed onward to kill him, hoping to satisfy their bloodlust…Unfortunately for them, this was the Doom Slayer and he was most certainly no normal man. He punched an Ursa so hard its skull shattered. Assuming it had an internal skull, that is. But the point was: It died.

BGM; Doom OST - E1M1 - At Doom's Gate

Several Creeps arrived but they were obliterated by the Heavy Cannon wielded by the Slayer. Some Beowulfs tried to attack him but he pulled out his Super Shotgun which just destroyed them in one shot.

A Beowulf tried to swipe at him, however, the Doom Slayer grabbed its arm and broke it. Then he twisted its neck which killed it.

A duo of Ursa tried to kill him but then he pulled out the Gauss Cannon, which has the Siege Mode on it. It quickly began to charge up and then he fired a piercing shot which instantly destroyed the two Ursas as a chunk torso were destroyed.

As soon as he was done he was besieged by a group of Boarbatusks. However, as soon as they got close, the Slayer performed a Blood Punch which caught the group as soon as they got close. They were instantly downed as the attack was able to kill them all.

Then several Griffons showed up in the air. The Slayer then pulled out his Super Shotgun with the Meat Hook and he grappled his way onto one of the Griffons which was also set on fire by it. It squawked in pain as the Slayer fired his Super Shotgun which destroyed its front portion. He then dashed forward and used his Doomblade to instantly cut in half another Griffon and then decapitated another one with ease. He then dashed again and ripped the head of another Griffon with ease.

The Slayer then grabbed ahold of the side of a ruined building to come back to the ground. As soon as he landed he was then punched in the helmet by a Beringel. It didn't do a lot of damage as all it did was make the Slayer mad.

He then rushed over to the Beringel and shoved his Super Shotgun up his mouth and squeezed the trigger of his most favorite gun, right up there with the BFG.

The Doom Slayer then saw that some Goliaths are approaching, but they were not moving in to attack as they realized he was VERY strong. More Grimm arrived as Beowulfs and Creeps arrived but then they were set on fire by the Flame Belch on the Praetor suit. As they were burning the Slayer then fired a grenade from his equipment launcher which exploded, killing them.

The Goliaths meanwhile waited as a Giant Nevermore arrived along with a Death Stalker though they didn't immediately attack and instead waited for the other Grimm to show up.

The other Grimm were mad as they couldn't actually kill him easily since he never seems to tire nor does he seem to be running out of ammo.

Luckily for them, reinforcements arrived, but not Grimm.

A portal opened up and out came a duo of Fireborne Barons alongside a plethora of demons which included Shotgun Soldiers, Imps, Hell Knights, Cacodemons, and Arachnotrons.

Somehow, the local monsters somehow knew that the demons were meant to assist them. As the newcomers didn't seem to want to attack the Grimm.

Now it was an "even" fight.

BGM: Doom - At Doom's Gate E1M1 remake by Andrew Hulshult

The Slayer simply pulled out the BFG 9000 which then fired a green ball that then has green strands of lightning attack the Demons and Grimm unfortunate enough to be close, which actually killed the weak ones but the Barons were able to survive albeit suffering from damage taken by the attack.

The Giant Nevermore and Death Stalker had to retreat alongside the Goliaths, though the Elephant Grimm were caught by the attack as the ball impacted one of them. As soon as it did it instantly killed the Goliaths unfortunate enough to be caught by the blast.

The slayer then pulled out the Ballista and charged up a Destroyer Blade, which was then fired. The attack instantly sliced in half Creeps, Boarbatusks, Imps, and an Arachnotron.

The Nevermore then swooped in and tried to shoot out a volley of feathers that acted like arrows from its wings at the Slayer, however, he dodged the attacks and then fired the Meat Hook after switching to his Super Shotgun at the Grimm. He came close to the Nevermore who tried to peck at him but got a Super Shotgun blast to the face. For extra overkill, the Slayer then sliced it with his Doomblade.

Then the Doom Slayer fired an Icebomb at the Two Fireborne Barons who were below him. He then pulled out his Chaingun and he activated the mobile turret mod of it. The quadruple barrels ended up mowing down the first Fireborne Baron in a blaze of bullets then he turned the huge gun at the next Baron who finally unfroze. Before the super heavy demon could do anything, the Slayer stabbed his Doomblade into the bottom of its head.

Then the Death Stalker actually managed to grab the Doom Slayer in one of its claws. The Grimm tried to crush him but it failed to do anything.

The Slayer pulled out one of his most favorite melee weapons, the chainsaw, which he then used to cut off the claw he was trapped in. The Grimm screamed in pain but was then silenced at his face was chainsawed in half.

BGM End.

The Slayer was done killing the Grimm and their demonic reinforcements. He was covered up from head to toe in blood. As for why he was there on Remnant, the Doom Slayer wants to clear humanity of the Grimm forever, and the demons plaguing the world as well, as he knows what is going on behind closed doors. Though of course, he couldn't have come sooner due to the fact that he was busy saving Earth from the Icon of Sin and also killing the Khan Maykr.

"Well, it seems that the demonic presence here is gone for now. However it is concerning that these Grimm and demons are working together," Samuel Hayden said. "Before we go to Vale it is in our best interests to annihilate the remaining Grimm nearby."

The Doom Slayer loaded his Super Shotgun and ran forward to go on a Grimm killing spree.

A/n: So the Slayer is now in Remnant, time for the Slayer's Grimm kill count to rise alongside his Demon kill count. Now you may be wondering who Salem was talking to…there's only one way to find out…