The distant sound of slugfire drifted through the air as Jacquelyn McKenna tore through the desolate town, leaning heavily over the neck of her mechabeast while nursing a bloodied arm. Teeth gritted, she swerved to avoid being impaled from behind by a large wooden stake, which had been aimed to execute her.

She could hear her enemy pursuing her with determination, and had to fight to keep her single eye forward, focused on her destination rather than on what lay behind.

To look back would be to die brutally, just as her girlfriend had died only hours prior.

Even the memory caused her stomach to leap to her throat, but she shook it away, lurching her mechabeast to the side in order to send it galloping down a narrow pathway toward an opening in a cliff wall. She pressed forward, charging full speed even as the sound behind her threatened to consume her. Every inch of her mind screamed at her to sling at her opponents, but she knew her slugs would have little to no effect on the monsters. In any case, the corruption of her teammates would only spell more doom for the caverns which already threatened to fall apart around her.

"Just a little further, " she told herself, trying to block out the hissing which tailed her. She had to make it — Layla couldn't have died in vain.

Shadows darted in front of her, blocking her escape just before she reached safety. Jacquelyn hit the breaks, and her elk mecha skidded to a halt as more shadows appeared, using the darkness to surround her. Teeth bared, they closed in, and the young redhead inhaled sharply.

"Now or never, guys, " she whispered, loading her wrist blaster with one of the snarling black slugs attached to her chest sash. "Give me a way out, Magma!"

With a burst of light, the ghouled Forgesmelter exploded from her blaster and transformed, spitting molten lava at the shadows. Those few which were unfortunate enough to be caught in her flames vanished in clouds of darkness, screeching madly while the others jumped back, hissing.

Magma returned to her protoform and landed on Jacquelyn's shoulder, snarling like a feral beast as the girl took off once again for the cavern entrance.

Just when she thought she would make it into the shelter of GlowStone Cavern, a dark figure appeared on her mechabeast, black hand curling around her throat and throwing her off the mechabeast. The stone wall broke her fall, but it wasn't much use. Before she could even register what had happened, the creature was on her again, white fangs mere inches from her face, fingers curled around her throat.

No mercy in those jewel-green eyes. Only madness.

The figure was bigger and stronger than Jacquelyn, and it didn't seem too keen on allowing her to live another second. Arms pinned, the redhead slugslinger couldn't defend herself, and the weight on her upper body was starting to constrict her throat.

Blurred images flashed in front of her. Layla smiling at her, holding her hand, kissing her cheek. A time of peace, of prosperity.

The image distorted, and suddenly she stood in front of Layla as the shadows tore her to pieces, limb by limb. The girl screamed at her to run, and those were the last words Jacquelyn heard before the shadows silenced her girlfriend forever.

All that was left was the burning in her own chest.

A burning which would now be doused as this shadow took her life, whispering in a tongue she did not understand, with the blood of both people and slugs coated on its hide.

Jacquelyn snapped open her eye as she heard a slug hit velocity, and a bright light engulfed her vision. The shadow disappeared, relieving the weight on her chest and allowing for her to sit up, just as a flaming beast soared by, twirling upward toward a small ledge where a lone figure stood.

The slug returned to its protoform, landing on the shoulder of the boy who stood there. Jacquelyn let out a shaking sigh, loading up a snarling black slug which was once an Arachnet, but no longer held the pure slug energy. As the spider-like creature transformed, it released a single strand of silk webbing, which the girl grabbed with her clawed hands. The Attacknet soared up to where the boy stood , shooting past him and only returning to his normal form when the girl landed on the ledge near the boy.

"Thank you, Junjie." She nodded to the other slugslinger, then to the slug who had saved her life. "And you, Joojoo."

The flaming slug saluted her.

Jacquelyn came to stand beside the boy, overlooking the damage being done to their caverns. "It's worse than it ever could have been." She told him after a moment of silence. "They've gone completely mad."

"I have never seen the ShadowClan behave in this manner," Junjie sighed, closing his eyes for a long moment. "Their rage is beyond my understanding. It is as if they've been corrupted somehow. Like how slugs and mechabeasts were once corrupted in the past."

The redhead narrowed her eye. "But that was in the days of the Emperor, and his Goon. I thought we had eliminated ways for corruption to occur."

"Perhaps we thought wrong," her cousin replied grimly. "We were wrong about many things. About being able to free your slugs from their corruption, about reasoning with these beasts who were once our allies."

"Is it even possible to ghoul the ShadowClan?" Jacquelyn demanded, crossing her arms, then wincing as the movement brought her great pain.

Junjie rose to full height. "Anything can be corrupted if enough dark energy is used." He beckoned to her. "Come. We must seek shelter and find any survivors in this cavern. Lucy is waiting in the GlowStone Caves."

At the mention of her twin sister, Jacquelyn felt her spirits rise ever so slightly. She followed her cousin, walking away from the ruins below them and emerging into a darkened cave filled with gleaming dark gemstones. Her ghouls were silent, obedient as she walked with the steps of a true shadow. As she entered after Junjie into a narrow passage, her single eye landed upon another woman observing some phosphoro slugs lined up on the walls. Looking at her was like looking into a mirror, for the girl she faced was her identical copy — save , of course , for the hair.

Twins. Sisters.

"Lucy," she breathed, moving forward to embrace the other girl. "I'm so glad you're okay."

The brunette girl wrapped her arms around Jacquelyn's midsection, burying her face into the crook of her neck. "I thought you were gone after I heard about the attack." She whispered, pulling away after a moment. "I also heard about Layla. I'm so sorry, Jackie."

The redhead pursed her lips, shutting her eye as the flashes returned. "We can talk about that later. I'm fine. We have to figure out how to fight off the ShadowClan before they lay waste to the Eastern Caverns."

Junjie nodded. "We have concluded that, like slugs, they have been exposed to Dark Water and corrupted, which has driven them to madness."

"Ghouled ShadowClan?" Lucy scoffed. "Now I've heard it all." On her shoulder, a ghouled AquaBeek snarled in agreement. Like Jacquelyn, the brunette's entire arsenal was ghouled permanently — a curse that the two had lived with for years.

"It's true," Jacquelyn stood beside their cousin. "The ShadowClan have been corrupted. Nothing else can explain why they suddenly turned against us."

Junjie nodded. "And they're killing slugs. The ShadowClan are noble creatures who protect and cherish all slugs in Slugterra. This is the ultimate betrayal. Only Dark Water could cause such a change in such a short time."

The walls of the cave rubbed dangerously around the three, and Jacquelyn clenched her fists, picking out a slug container with a snarling speedstinger within.

This slug had been ghouled along with her others long ago, and no amount of Boon Docs had been able to cure him or the others of the corruption. Each of her slugs was special and important to her, but this one, however cruel she could be, held a very special place in her heart.

For this little slug, once innocent and sweet, had been Layla's very first gift to her, many years ago.

Now, it was all she had left of the girl she loved.

"Keep us safe, Trickshot," Jacquelyn whispered, aiming the ghoul up at the ceiling. She fired, watching the speedstinger transform and strike one of the stones, bouncing off and hitting the wall off to the right, then using the floor as a third launchpad before finally shooting toward the cavern entrance. Just as one of the ShadowClan appeared, Trickshot struck, slamming into its head with a sickening crack.

"They've found us!" Junjie warned, just as Jacquelyn snatched up her slug and inserted it back onto her sash. "Jacquelyn, do you have the Forevermore Slug?"

The redhead snapped her gaze up, dropping her arms.

"She is not in your belt." Her cousin pointed out, only to pause when a large silver slug poked out its head from the mess of red hair which had come loose earlier in the fight.

"I'd rather lose my life than lose the only slug in the known world who can't be ghouled." Jacquelyn smirked, lifting her hand so the slug could jump on.

Junjie nodded, then looked up as the walls trembled violently. "They will break through at any second. We must get out of here."

Lucy stepped forward, lips pursed into a grim expression. "The ShadowClan won't rest until they get what they're after."

"We can fight—"

"No." Lucy cut off the Eastern Champion with a sigh. "No, Junjie. We can't. The Eastern Caverns are falling apart. Too many slugs have been lost already. We can't lose anymore. You have to leave. Get to the Western Caverns. The ShadowClan can't follow you there."

Jacquelyn stepped forward, narrowing her single eye. "Don't you dare tell me to leave you behind, Lu. You're my twin."

"But you are the wielder of the most powerful slug known to man." Lucy argued. "She is your responsibility, and you have to protect her. We all do." She turned away, loading a ghouled Flaringo into her blaster. "Go, Jackie. I'll hold them as long as I can. It'll buy you time to get to the crossing point."

"Lu, no. I can't lose you. Not like I lost Layla. I won't be able to take it."

"Yes, you will. You're strong, Jac. Stronger than anyone I know. You'll make it through this." Her older twin let a small smile creep onto her lips. "Take Soaker with you. He's your burden now." As she spoke, her ghouled AquaBeek jumped from her shoulder to Jacquelyn's, growling softly. Lucy turned away, aiming at the entrance. "Go, now Jac!"

Junjie grabbed Jacquelyn's wrist and dragged her onto his mechabeast, charging into the shadows of a tunnel which sloped downward dramatically. Slugfire echoed around her — Lucy's final stand for the protection of her family and the caverns which they could not save. The further down she traveled, the more faint the sound above became, until there was nothing but the eerie howl of the underground wind and the faded sound of dripping water.

"Here." her cousin released her arm, his mechabeast stepping into an open cave glowing with a faded blue light. "The Gateway."

"Where are the Gatekeepers?" Jacquelyn asked, her voice numb with shock and pain.

"The Guardian Slugs have fallen already. Which means we still have time to get through to the West before the portal falls," Junjie glanced back over his shoulder, his tone dropping slightly. "But the ShadowClan are pursuing."

Jacquelyn let out a sharp breath. "Then let's go."

Junjie dismounted his mechabeast. "Drive straight into the light. Don't look back, don't stop. Not until you are safely through to the other side."

She arched her brow. "What about you?"

Her cousin loaded his blaster with a Frostcrawler, looking her dead in the eye. "The Eastern Caverns are my responsibility. I will not abandon it now."

Jacquelyn's stomach lurched. "You don't have to stay. Lucy gave her life for you to escape."

"She gave her life for you, Jacquelyn. Not for me. This is where I make my final stand. The ShadowClan will not come after you through this portal. I won't allow it."

The redhead closed her single eye, fighting back the tears burning at her core. The lump in her throat grew bigger. "It isn't supposed to end like this."

Junjie placed a hand on her shoulder. "All of our stories come to an end, Jacquelyn." He told her, sighing as he pulled a slug barrel from his chest, placing it on hers. "But as this one draws to a close, a new one will begin. With you as the new Eastern Champion."

Jacquelyn looked down at the new slug barrel, her eye meeting those of Joojoo, the prized Infurnus of Junjie. She looked up. "Junjie, no, I can't take —"

But her cousin had already turned away, blaster aimed now at the narrow entrance. "You can and you will take him, Jacquelyn. Joojoo represents everything the Eastern Caverns have fought for, and as the Champion, I may pass him on to whomever I choose."

"I'm not a Champion, Junjie. I can't wield the Infurnus that is yours by blood." Jacquelyn croaked.

Her cousin turned his gaze back onto her, his eyes holding nothing but peace and serenity. Seldom had she seen the Eastern Champion angry. He glanced down, toward the slug he had gifted to her. "Take care of her, Joojoo." He told him, before turning and charging back into the tunnel, blaster pointed forward.

Joojoo nodded determinedly, before jumping up and forcing the mechabeast into gear. It bolted forward, heading straight for the portal that would lead to the Western Caverns. The world crumbled around her, but as the light engulfed every part of her body, Jacquelyn felt her consciousness break away.

Until she was only aware of the distance lullaby her mother once sang to her.

Then, all was silent.