After giving Rainbow another med-syringe and bringing Fluttershy back into consciousness, the group walked around the stumps that the Cyberdemon had left and headed to the back of the throne room. There, a panel in the wall was decorated with various pictures, most of them meaningless to Grimm. A single hole was on the wall, and Celestia went to put her horn in it, but stopped. "Oh, right, no magic..." She trailed off, sounded slightly defeated.
"Then we'll use the magic of heavy ordinance. Stand back," Grimm ordered while taking out his rocket launcher once more. The ponies all stood back as he opened fire. After three rockets, the marine stopped shooting, letting the dust clear. When it did, the panel was destroyed, revealing a room behind it. Celestia went up to the rubble, but was distraught upon looking inside the room. It wasn't as simple as the box containing the Elements being there, ready to use. Instead, it was across the room. In between the entrance and the box, was a lowered floor, spots of dried blood here and there. The princess went to retrieve the Elements, but Grimm stopped her.
"It's a trap, I just know it." Cautiously, he walked in, looking all around. Sure enough, there was a path for getting to the Elements on the ceiling. The marine wasn't certain what would happen if he strayed from that path, although it was a safe bet that it wasn't anything good. He began following the predetermined path slowly, each square of floor he moved over raising up to the level the floor which the box sat on was. Eventually, he got to the other end, and picked up the box containing the Elements of Harmony. Grimm was making his way back, following the same path, when he tripped and placed a foot on a part of the ground that wasn't raised. Suddenly, the room started shaking.
'Oh shit.' Foregoing caution, Grimm sprinted back to the entrance, careful not to trip over the raised floor. Just as he made it back out, the ceiling came down loudly inside the chamber, sealing it off. Grimm dusted himself off, before holding out the box. "Those Elements you wanted?"
Celestia opened the box, not used to using her hooves. Inside, the six Elements of Harmony sat. Out of habit, she tried to pick them up with her magic. When that failed, she looked to Grimm. "Could you... put them on Twilight and her friends?" She was grinning sheepishly, while the human sighed.
After outfitting the ponies with their Element, Grimm decided to sit back and see what they'd do. Discord did the same, still sitting in that theater chair. Convinced that they were out of earshot of the ponies, Grimm spoke.
"You can still use magic, can't you?"
"Yes, actually, although not much. Just basic teleportation and chaos-making."
"So you could've gotten the Elements yourself this whole time, and saved us all this mess?"
"I could have, but where's the fun in that? Besides, you seemed to enjoy yourself when fighting."
Grimm wanted to get mad at Discord, but he couldn't. The draconequus was right. "Well, I do seem to have a perverse enjoyment of killing demons. Guess it goes well with what I do."
"After that slaughter, even I feel nervous around you.
Grimm chuckled. "You should've seen what I was doing when I first got here. Let's just say that that chainsaw of mine saw some pretty heavy use."
The two drifted off into silence, watching the Elements of Harmony at work. Somehow, they still had magic in them, and a giant rainbow-colored beam of light shot up and through the ceiling. Soon, the entire castle was bathed in light, and Grimm had to shield his eyes. When he looked again, the area was decidedly less demonic looking. Even the Cyberdemon corpse was gone. The throne room was still heavily damaged, however, with multiple holes in the walls.
Celestia lit up her horn, and smiled. "We have taken back our castle. It will have to be repaired, and there are still the deaths of good ponies to mourn, but we couldn't have done this without you, John Grimm."
"We're not quite done yet." Despite the uplifting mood, Grimm's face was still serious. "The demons are going to come back, and keep coming back, until they win. Unless I go to the source and chop it off there." He turned to Discord. "You, you said that they had a portal here, right?"
"Yes, they had one."
Her horn growing brighter, Celestia frowned. "Yes, I sense it... It's the last trace of the demons left in the castle."
"Then show me where it is."
The other ponies were a bit shocked by Grimm ordering Celestia, the ruler of Equestria, around, while Discord was amused. Regardless, she led the way.
They entered into a separate room, not that far from the throne room. It was slightly damaged, yet normal, save for the glowing, red pentagram on the ground. It crackled with a sinister energy, causing even the princesses to back away a step. Grimm, instead, chose to walk towards it. Just outside it, he turned.
"Now, I understand you wanting to tag along here. After all, it was your castle. But here's where I say goodbye. I'll be going through the worst that those demons have, and I'll go it alone, same as always. Good luck on that whole 'rebuilding' thing. Maybe I'll see you again. Maybe I'll die in there. Heh, who knows?" Before any of them could stop him, he leaped in, disappearing in a green flash of light. Not a trace of the human was left in the room. The pentagram still glowed ominously.
"I can't believe he just left like that..."
"I won't get to throw him a 'Thanks for saving Equestria' party..."
"Ah'll say one thing, he's braver than any o' us."
"Quite chivalrous, even if it might be a bit... bone-headed."
Twilight looked around. "Wait, what about Discord?"
She was answered by another teleportation from the pentagram. Just outside it was a small note, reading:
BRB, went to Hell.
Discord
The note was attached to a small cotton candy cloud, which Pinkie snatched up quickly. The princesses looked at each other.
"What do we do now, Tia?"
"I may have an idea... But for the most part, we can only hope."
They all looked at the pentagram, only wondering what the marine could possibly be going through now...