All of the ponies recoiled away from the magical projection with shock. This new creature was bigger than any they had seen, and Twilight noted that it was bigger than the giant demon Grimm killed shortly before arriving in Equestria. They watched as Grimm barely evaded the creature's attacks, mostly consisting of a lot of fireballs and throwing lava. Lesser demons would appear around the giant chamber, forcing the marine to mop them up before focusing on the big one again. None of his weapons seemed to harm the creature at all, though; even his largest gun barely left a scratch. Upon seeing this, Celestia made up her mind.
"We are going there."
Everyone else let out a collective "What?!" at this.
"But Princess," Twilight said, "You've seen how dangerous that place is! What if-"
"And you've seen that creature that Grimm is fighting. He has no hope of defeating it alone, and Discord doesn't seem to be helping much. So we will have to go there and use the Elements of Harmony on the beast."
One by one, the six ponies agreed. Luna joined them, but the elder sister stopped her.
"Luna, I want you to stay here."
"What? But we- I mean, I want to help!"
"Yes, but I'm not entirely sure if I will be coming back. We need someone to rule over the kingdom in case I can't, and that someone is you, dear sister."
Luna was about to argue, but she nodded. The two sisters shared a hug. "Please... come back."
"I will do my best." The two separated, and Celestia went to the Elements. Grouped together, she began casting a teleportation spell, before they all vanished in a bright flash of light.
"God damn it! Just die already, you son of a bitch!"
Grimm had been shooting at the giant demon for a few minutes, and it didn't show any signs of tiring or even being hurt. There was ample ammunition available around the chamber, thankfully, but it didn't change the fact that this thing was nearly invincible. It was quickly grating on the marine's nerves. The constant spawning of other, much more killable demons did nothing but waste his time, ammo, and patience. Even the BFG, the holy grail of armaments, did seemingly nothing to this beast. Discord was doing almost nothing useful. He tried his magic on the thing, and it didn't work, so he simply took it upon himself to act as an "eye in the sky" for Grimm. This was hardly needed, though, because Grimm could always tell where the demons were.
Wanting to reload his guns and take a breather, Grimm dashed behind a rock, safe from the constant barrage of fireballs- For now, anyway. While reloading, he looked to the side and spotted a rock wall that looked climbable. Looking at the ceiling, it looked traversable, too. 'Maybe if I can climb up there, I can get close enough to that bastard without burning my-'
His thoughts were interrupted by a bright flash of light behind him. Whirling around, shotgun raised, he came face to face with Celestia and the Elements of Harmony. He lowered his gun before speaking. "What the hell are you doing here?"
"We're here to help you out," Celestia replied. "The Elements of Harmony can be used to help defeat this vile creature."
"I'm not gonna ask how you knew I was in trouble, but I'm gonna go ahead and assume that magic was involved."
Lazily, Discord floated down. "Oh, what joy, the Elements of Harmony are going to save us all," he deadpanned. "What, are you going to lock it in stone? Because that worked so well with me."
The princess glared at the draconequus, before turning back to Grimm. "Just let us try this, unless you have a plan."
"As a matter of fact, I do. I'm gonna climb up there," he pointed to the wall, "and get close enough that I can shoot it point-blank. Now that you're all here, maybe you can run interference for me."
"I'm sorry, I don't catch your meaning."
"What I mean is, you can all distract it long enough for me to get in place." Celestia looked appalled for a second, but she nods.
"Very well, I suppose." She turned to Twilight behind her. "You know what to do."
While they were preparing, Grimm ran off towards the wall. He mowed down any demons in his way with his chain gun, trying to get there as fast as he could. As he started climbing hastily, he overheard Twilight speaking fairly loudly.
"Okay, you... er... beast! We will not let you hurt anyone, pony, human, or whatever else, ever... again!" She didn't seem to be good at delivering dramatic speeches, or at least not in this situation. The heat probably wasn't helping matters. Thankfully, just as planned, the behemoth focused on the ponies. At first, it didn't do anything, probably from sheer confusion. While Grimm kept climbing, Twilight went on to name her friends and what Element they were: Applejack, Element of Honesty; Fluttershy, Element of Kindness; Pinkie Pie, Element of Laughter; Rarity, Element of Generosity; Rainbow Dash, Element of Loyalty; and Twilight herself, who was the Element of Magic. Grimm would had laughed at the corniness of this, if he wasn't being attacked by those damn flaming skulls. He couldn't use his guns effectively while climbing, so he used his free hand and smashed them on the rock face, bone fragments raining down below. As he made it to the ceiling, the giant creature regained its senses, and started tossing fireballs at the ponies. Celestia was one step ahead, though, and put up a shield around the Elements.
Thankfully, the ceiling had a series of small caves in it, so Grimm didn't have to cling to the ceiling by his hands. He got into place just above the behemoth, and Discord warped right beside him.
"Don't mind me, I'm just here to see what it's like when the Elements are used against someone who isn't me."
Grimm shrugged and got a rappel cord tied to a sturdy rock and attached it to his belt. He sat and waited for the Elements to hit, in case it actually did do something. Twilight finished her speech, and another giant rainbow beam shot out from the group. It headed straight for the demon, who was obscured by the light. When the beam faded, the demon stood there, now with a large hole in its head, exposing brain. Realizing this opportunity, Grimm took out both his BFG and chainsaw, revving up the latter.
'Here goes nothing.'
He jumped out of a hole in the ceiling, swinging towards the giant demon. Just as he was about to hit it, he brought the chainsaw forward. It hit, embedding itself several inches into the skin of the demon. It roared in pain, trying to buck the marine off, but he held on. Before it could bring its claws up, he aimed his BFG at the exposed brain. As it hummed to life, he said:
"They forgot me, the Element of Ass-kicking."
The gun fired, making the demon let out an ear-splitting screech before toppling over. Grimm hung onto the chainsaw for dear life, until the demon's impact with the lava sent both him and the power tool flying back to the rocky ground. The entire chamber began shaking, chunks of rock falling from the ceiling, demons swarming all over the place.
"Grimm! Come on! We have to get out of here!" Twilight yelled.
"Just go!" Grimm shouted back, in the middle of combat. "Don't worry about me, just get out of here!"
"But-"
"I said get the fuck out of here!" Begrudgingly, Celestia cast the teleport spell again, preparing to go back to the castle. Before they left, the last thing they saw was Grimm standing on top of a pile of rocks, chaingun in one hand, shotgun in the other, fighting off dozens of demons.
It had been hours since Grimm had killed the giant demon, and now the rest of them were dead. He knew what he had chosen, and he knew what it meant. He was going to stay here in Hell, and make sure that they don't invade Earth, Equestria, or anywhere else, ever again. A couple of magic letters appeared to him, from the ponies he had met, and he had to use the burning corpse of an archvile to send back that he didn't want to be "saved", and to tell them what he planned to do. Because of the lack of letters in response, he figured that they accepted that. And even if they didn't...
'...then tough shit.'
Now Entering: Epilogue
