Gajeel and Gray stood glaring at the giant fire Spider-like Demon, who in turn, was glaring at them.

Gajeel: We ain't got time to deal with you bug-boy. Now get lost!

Phantom: Foolish Dragon Slayer! I will not be swayed so easily, prepare to die!

Gray: You first!

Phantom roared and blasted a large motel fire-ball from his mouth, causing Gajeel and Gray to scatter to the sides of the chamber.

Gajeel: Iron Dragon Club!

Gray: Ice Make: Lance!

Both their attacks barreled for Phantom and each made direct contact, forcing the demon back. But it was able to jump high and land behind both of them. It roared before it's massive behind opened to reveal a scorpion-like tail; which then made a thrust for Gajeel, causing him to jump back. It then thrusted towards Gray, making him jump back as well.

Happy: Hey that's not fair! Spider's aren't supposed to have tails!

Carla: It's a demon, not a spider.

The two were flying in the air at a safe distance.

This demon move at impressive speeds for something that was rather large. Phantom roared as he lunged his stinger towards Gray. 

Gray: Ice Make: Shield!

Gray formed a rose-shaped shield which took the impact from the stinger, this gave Gajeel his opening.

Gajeel: Iron Dragon Sword!

Gajeel's right arm became a jagged sword and he jumped high and delivered a large slice to the tail, cutting it off completely.

Phantom roared in pain, but Gajeel's victory turned painful as he felt his sword becoming hotter. Some of the magma that came from Phantom stuck to his sword and he was forced to discard the metal. He watched as the molten metal melted.

Gajeel: Damn that's hot!

Phantom: Curse you human!

Gray: Look behind you ugly! 

Phantom turned around to Gray as he jumped onto Phantom and placed his hands over his body.

Gray: Freeze!

Ice began to flow and quickly cover Phantom. He tried to struggle and grunted in pain as the ice completely covered his body until he stopped moving all together. Both wizards took the time to admire their work, as did the two flying cats.

Happy: Alright! Gajeel and Gray are awesome! They took that demon down no problem! 

Carla: I wouldn't celebrate just yet, that was too easy.

Gajeel took a few whiffs and growled as he didn't like what he was smelling. 

Gajeel: Fullbuster...

Gray: I know, we're not done yet.

Steam began to form all around the frozen Phantom. Cracks in the ice began to form as they cracked further and further, until finally, Phantom exploded out of the ice with a massive roar.

Happy: Whoa! HE'S STILL ALIVE!!!

Gray: Somehow I knew it wouldn't be that easy.

Phantom: Recess time is over kiddies! Both of you will die here and now!

Gajeel: Bring it, freak!

Phantom roared and charged at near lightning speed, blowing the two wizards back as Phantom soared to the other end of the room. Phantom did the same thing again and barrelled straight for Gray. Using his head, he slammed Gray into the wall.

Gajeel tried to come in from behind, but Phantom quickly turned around and swung his two front legs, knocking Gajeel back and smashing him through one of the pillars that decorated the large chamber, causing the room to rumble a bit. Gajeel soon recovered and got back up. 

Gajeel: Iron Dragon Roar! 

He blasted a torrent of metal shards from his mouth which hit Phantom dead on, but he exploded in a storm of lava and Phantom used the force of his blast to land on the ceiling. 

He stuck to it and began to shoot fire balls from his mouth at Gajeel, which rained down at him like meteors.

Gray soon got back up and put his hands together to make another ice construct. 

Gray: Ice Make: Cannon! 

He formed a bazooka out of ice. He shot a massive ball of ice that soared at Phantom like a rocket and hit the demon dead on. 

But Phantom used his momentum to fall towards the left wall and stick on it like a spider.

Phantom: You are really starting to annoy me! 

Phantom began to fire at Gray again. These meteor fireballs all head towards Gray and he was quick enough to run, jump, and avoid all of them. With Phantom's attention focused solely on Gray, Gajeel got his opening. 

Gajeel: Iron Dragon Lance: Demon Logs! 

He formed a spear in his right arm and began to fire a series of green energy beams from it like a machine gun.

The attacks grazed Phantom and forced him to crawl quickly across the walls. Gray then got into a stance and prepared another spell. 

Gray: Ice Make: Lance!

Gray began to shoot multiple ice-lances at Phantom, while Gajeel kept his attack going.

Both attacks shot towards Phantom rapidly as he crawled all along the walls and ceiling at rapid speeds and the attacks all hit behind him as the two wizards kept shooting at him.

Happy: That bug demon is going hit for hit with both Gray and Gajeel!

Carla: Of course, he did say he was one of Mundus' strongest demons. 

She observed the battle and tried to find a way to bring this demon down. 

Carla's mind: Phantom is too fast for either of them to land a clean hit. If there was a way to pin him down... 

Carla then remembered when Gajeel smashed through one of the pillars the room shook. She had a realization and looked to see on the left side of the room, there were six large pillars, and five more on the right side. (not including the one Gajeel accidentally broke).

Carla: We have to bring the room down! Tell the others.

Happy: Got it! 

Happy flew down to the level where Gray and Gajeel kept shooting towards Phantom, hopping to hit the fast-moving demon.

Happy: Guys, we need to bring the room down onto Phantom. It's the only way to beat him! 

Gray looked to the pillars and knew what Happy was talking about. 

Gray: Gajeel-

Gajeel: I heard! You try and get that overgrown bug to slow down!

Gray: Got it! 

Gray stopped his attacks and placed both his hands on the floor.

Gray: Ice Make: Floor! 

Ice began to spread all along the floor, but Gray wasn't done yet. 

He kept pouring much of his magic energy into his spell and ice began to spread over all the walls and ceiling, and even covered the pillars until it looked like the entire chamber was made out of ice. Phantom then began to loose his traction on the wall. 

Phantom: What?! What is this!? No!

Phantom lost his grip and roared as he fell from the wall and landed hard on the floor. He tried to get back up, but found himself unable. He looked to see Gajeel and Gray both jump high in the air.

Gajeel: Iron Dragon Club! 

Gajeel's right arm became an Iron Club and stretched as it broke through all the pillars on the left side of the chamber.

Gray: Ice Make: Cannon! 

Gray formed his Ice Cannon again and shot a large Ice Ball that blasted through all the remaining pillars on the right side of the chamber.

The Ice weakened the pillars enough to allow both wizards to break through with their attacks. Phantom realized what they were doing and his eyes widened with shock as he roared. The entire chamber began to shake as the ceiling started to collapse. 

Large chunks of ice, followed by stone rubble began to fall. Phantom tried to run, but he was unable to keep his traction on the icy-floor, so the ceiling fell on top of him.

As the ceiling began to fall, Gajeel and Gray jumped from rock-to-rock to avoid falling and getting crushed. Carla quickly came and swooped up Gray and Happy did the same for Gajeel. 

Both cats took their passengers and found an opening, allowing them both to escape outside and watch as the outside of the chamber gave in.

Happy: Looks like we squished a bug.

Carla: (sarcastic and sweat dropped) You're hilarious. 

Gajeel: We're not done yet.

Happy: (question mark appeared above his head) Huh?!

Gray: He's right, look! 

Gray point down to the rubble below and saw Phantom attempting to dig his way out.

Phantom: Ignorant Humans! How DARE YOU!!!

Happy: He's not dead yet?! Are you kidding me?!

Carla: He's strong, I'll give him that much.

Gray: Just how much punishment can that over grown freak take?!

Gajeel: Drop me.

Happy: WHAT?! YOU WANT ME TO DROP YOU!?

Gajeel: JUST DO IT, CAT!!!

Carla: (lightly scold) No need to yell.

Happy: I hope you know what you're doing.

Happy dropped Gajeel and watched him fall towards Phantom.

Phantom continued to try and dig himself up, but found himself unable to. 

Phantom: I will not be defeated! I WILL NOT LOOSE TO THE LIKES OF YOU!!! 

Gajeel: (fell towards Phantom) Oh shut up will you?! Dragon Slayer Secret Art: Karma Demon, Iron Spiral!

Gajeel's lower body transformed into a massive iron drill that barreled straight down for Phantom. 

Phantom: NNNNNOOOOOOOOOOOOOO!!!!!!!!!!!!!!!!

Gajeel's attack landed, resulting in Phantom exploding; which was seen from that side of the massive castle.

Happy: Okay, now I'm sure that got him!

Gray: Sure looks like it.

Carla: Does he always go this overboard?

Happy: Aye, that's Gajeel for ya!

Cave

Dante slid back as he glared at the giant demonic blob-like creature that was Nightmare. The blob then took the appearance of a humanoid-like creature with large arms.

Dante: I don't got time for this. 

Dante pulled out Ebony and Ivory and shot at Nightmare, but the bullets didn't have much affect as they just stuck to Nightmare's blobish body and sunk into it.

Nightmare roared as it tried to bring both it's massive arms down onto Dante, but he jumped out of the way just as the fists smashed into the ground. Dante landed on the wall and jumped forward with Rebellion out and slashed through Nightmare, cutting it in half.

Dante slid to halt as the two half's came together and melted back into one. Nightmare roared as a large white sphere revealed itself in its chest and began to shoot multiple white spikes towards Dante. 

He was quick enough to avoid them, but they continued to shoot towards him like machine gun fire. Dante was forced to run onto the ceiling and behind Nightmare.

Dante: Nevan! 

Dante quipped his electric scythe, which he used to send a massive bolt of purple lightning; which hit Nightmare dead on. But it appeared unaffected; Dante was beyond frustrated at this point.

Dante: Doppelgänger! 

Two duplicates of Dante appeared next to him and all three ran towards the giant blob. The left duplicate struck Nightmare hard on the left, the right duplicate did the same thing on the left side, and the real Dante brought Rebellion down on his head.

All three Dantes slid to the other side of Nightmare before the two duplicates vanished in a puff of dark smoke. Nightmare's white sphere revealed itself again.

Dante: You've gotta be freaking kidding me.

The white energy bullets shot towards Dante again, forcing him to jump high.

Dante: Agni! Rudra! 

Dante pulled out his two short swords and sent a massive gust of fire and wind straight at Nightmare. The attack came close to its white sphere, causing it to pull the sphere back. Dante jumped back.

Agni: Wait, did you see that?

Rudra: Yes brother, I did see.

Resulting in Dante slamming their heads together.

Dante: Remember when I said, no talking? (dodged another punch from Nightmare)

Agni: But we saw something that could be of great importance to you.

Rudra: Yes, a possible weakness in this monstrosity. 

Dante continued to dodge all the rapid punches that came from Nightmare's blobish body. Dante raised an eyebrow at their statement.

Dante: What kind of weakness?

Agni: That white sphere.

Rudra: When our attack came to close, it pulled the sphere back.

Agni: Meaning it did not want it to be damaged.

Rudra: It must be some kind of weakness.

Dante considered their statements as he dodged Nightmare's seemingly never-ending attacks from the white sphere. He didn't have anything else to go on, and he didn't have the time to play around with this demon.

Dante: Alright, I'll give your theory a shot, thanks guys. Quicksilver!

A cyan circle formed around Dante and he moved at a speed that was faster than lightning. He charged straight for the exposed sphere. Fire formed around Agni's blade, and Wind formed around Rudra's blade. He slashed with both blades on the sphere like an x.

The Fire and Wind seeped into the sphere and caused it to explode. Dante slid back to a safe distance and watched as Nightmare grew even large and bore the appearance of a sphere that was ready to pop, until finally...

*BOOM!*

Nightmare had exploded, and Dante shielded his eyes. He looked to see there was nothing left of Nightmare.

Angi: Impressive...

Rudra: ...As usual. 

Dante slammed both their heads together again. 

Dante: Thanks for your help, but remember...

Agni: No...

Rudra: ...Talking.

Dante: Good.

He was finished here. So now he ran to leave the cave and inevitably confront Vergil.

Chapter 15 ended.