A/N: A quick update because I know the last chapter was a bit confusing. I knew that going in so I kept it short. This chapter is longer and hopefully clears up anything that may have seemed odd. If you still have questions, let me know in the comments and I'll clarify the, for you. ^_^

Chapter summary: In which the universe is truly complex and two Akhs are not happy.

What Truly Matters

"Someone care to explain?" Diana said coldly once she recovered from the surprise.

"It is as Arrow said," J'onn said, speaking suddenly. "He does not know us. His mind is...ancient. Older than I remember Kaiba's ever feeling." The Manhunter's yellow eyes narrowed. "And he wants us to leave."

"And the feathers?" Wonder Woman asked.

She could not help but notice the numerous speckled feathers sprouting from Kaiba's head, mingling with his short brown hair as if they were a part of him. Glacial blue eyes which she now thought resembled a falcon's eyes more than a human's stared directly at her as if attempting to pierce her soul. Glittering tattoos of detailed feathers that caught the light from the electric bulbs and flickering flames flowed down muscular tan arms, rippling and shifting as if they were real and not mere renderings by an artistic hand.

The being that was and was not Kaiba wore a white shendyt, pleated and gathered in the front. A woven sash trimmed in gold in the shape of feathers bound the shendyt tightly to his waist. A blue shirt that was almost the same shade of blue as Kaiba's. Feathered wings spread wide from an amulet of blue emblazoned with the Set symbol formed a thick torque-like necklace which hung from the not-Kaiba's throat.

"He's a ka," Yugi said, coming up beside Diana. He rubbed a hand along the cut near his hairline, staring at his hand when he pulled it away and wincing at the blood. "Ka are thought to be duplicates of the human they once were. But something many people forget is that the ka does not mimic the body, it mimics the ba. They were a mirror image of their formerly human form until after the body's death."

"The ba were often depicted a birds with human heads or humans with feathered wings," Yugi continued. "That was not an artistic depiction, it was as accurate as the ancient Egyptians could get. The ka were reflections of their ba. The more powerful the ba, the more human the ka appeared. There's more but that's not important. What is important is that in ancient Egypt, the ka served two main purposes: they provided life to the living ba's body and protected it after death, forever bound to the darkness of the tomb until the ba returned from its daily flight under the sun. If the ba died or never returned by sunset, the ka would die."

"But Seth isn't dead. He's here," Wonder Woman countered.

"True, but Kaiba doesn't know that the way he is now," Yugi said solemnly, his eyes sad. "That...is no longer Kaiba. That's Set's ka. Without Mokuba awake to calm him or a ba he recognizes as his own, Kaiba has returned to being Set's ka with no purpose save to protect the empty shell he once gave life to and wait for death. It's all he knows, all he has."

"Okay, then how do we fix this?" Wonder Woman asked.

"We don't," Yami said, appearing beside Yugi, an arm thrust protectively between Set's ka and Yugi. "We've tried. Seth and Mokuba are the closest thing we have to a chance at saving Kaiba now. If we can keep Kaiba from attacking or escaping, it could give Seth and Mokuba a chance to bring him back."

"Right." Wonder Woman stiffened, looking around the room for someone she only just realized was missing. "Where's Ishizu?" she asked.

"She was giving Mr. Bakura and Carter a very significant piece of her mind when we left her," Yami said, a wicked grin on his face. A cry followed by dull thuds from the chamber behind them emphasized his point. "Kaiba didn't appoint her as his de facto leader without reason."

Diana smirked. "I would enjoy getting to know her better," she said.

"Why hasn't he attacked us yet?" Arrow asked warily, nodding to the mtionless ka.

"Because we aren't attacking him," Yugi said. "If we make a move he deems threatening, he will attack. But not until then."

"He's also tiring," Yami said. "A ka can only manifest like this within the tomb in which its former body was buried. I supposedly did something similar when Yugi's Grandpa entered my tomb and found the Millennium Puzzle I was imprisoned in. I don't remember it..."

"But Grandpa does," Yugi said gently.

"If you don't remember it, then does that mean Kaiba won't remember this?" J'onn asked.

"Probably not," Yami confirmed. "Seth! Is Mokuba alright?"

"Yes," Seth called back, standing. Mokuba was sitting up now and rubbing the back of his gingerly, eyes never leaving Kaiba. "Do not attack. Let me try again."

"Be careful," Yugi said, pushing Yami's arm down to stand next to his ka, tangling their fingers together. :Do you think it might come to that?: he asked mentally.

:Let's hope not,: Yami replied, glancing at the Justice League members next to them.

"You said he was tiring," Arrow said to Yami, taking care not to appear threatening while still ready to attack at a moment's notice. "What did you mean by that?"

Yami's eyes narrowed. "No one's strength is limitless except Ra-Horakhty's. A ka's power depends on its spiritual strength and its connection to its ba. But without a ba to protect and root it, its power is nowhere near as strong as it should be."

"And Seth isn't buried here," Arrow murmured, eyes shifting to the ba still possessing Kaiba's body.

"Precisely."

"If Seth can convince Kaiba to return on his own body, it should not be too big of a problem," Yugi said. "We have a backup plan in case things don't work out."

"What kind of plan?" Arrow asked. He never got a reply.

"Wonder Woman," Yami said instead, "keep your lasso ready. We may need it."

Seth stood tall, wincing from the jab in his side where a trunk corner had hit him when Kaiba blasted him. "Seto," he said softly in hieratic, taking a wary step forward. "I am not a trespasser here. This was my resting ground just as much as it was yours." Another step. "But we do not need this place anymore, Seto. We were reborn, you and I."

He took another step and the ka that should be Kaiba shifted, lifting its arms from its sides slightly. It was only then that Diana realized the reason for the rippling movement of the feathers on the ka's arms. It was layers of feathers that spread out from the ka's arms to two points between its shoulder blades. Wings.

Seth stopped his approach and stood still. He was within arm's reach of his ka, the closest anyone had managed to get without being brutally attacked. It gave Yugi hope that somewhere deep in the ka's mind Kaiba was still there. Seth lifted his arm slowly, palm upwards, and held it out halfway between himself and his ka.

"Touch me," he said in hieratic. "This body belongs to you. I am your ba. You need not trust my words. Trust what you feel."

Indecision and distrust darkened the ka's eyes, but that was a step up from the empty nothingness that had been there earlier.

"Mokuba," Seth said in Japanese, the tone of his voice even and gentle, unthreatening. "Call for you brother."

The younger Kaiba stepped out from behind Seth in his big brother's body and stared up at the spirit that should be his big brother. "Nii-sama?" he called in a voice that was almost a question.

The ka froze, its birdlike eyes widening and focusing on the little boy. It head cocked to the side sharply in a fashion that was, again, more avian than human. Despite its alien feel, it filled Mokuba with hope.

"Nii-sama?" he said again, this time louder, braver. "It's me. Mokuba. Remember me?" The ka did not move. "You promised we'd always be together, that you'd never leave me." The blue falcon eyes shifted edged with an emotion that had not been there moments ago. "You never break your promises," Mokuba said firmly. "You taught me to always keep my promises." The boy's hands curled into small fists and tears pooled in his dark gray eyes. "So don't break your promise to me. Come home."

The ka did not move, but its eyes gleamed with emotion and indecision. Everyone waited for a response, any kind of response. But there was nothing. Then, finally, the ka extended its own hand and placed its fingers gingerly on Seth's open palm. The people in the room released a collective sigh of relief. It was a pity it would be so short lived.

"A ka," a voice whispered. "A true ka."

Yugi whirled around as did Yami and the rest of the group. Only the ka that should be Kaiba did not move.

"Mr. Bakura?" Yugi gasped. "But...Ishizu..." His voice fell away when he noticed the crumbled forms of Carter and Ishizu on the floor beyond. But that meant the thuds from before had been...

"Keep him away from us," Seth said calmly, capturing his ka's gaze with his own and holding it steady. "Do not let him distract us."

"Gladly," Arrow said, lifting his bow and pulling the string taunt, aiming directly at Mr. Bakura's head, ready to fire when necessary.

"Mokuba," Seth said gently, "stay close to us."

Mokuba nodded and scooted closer to Seth. He stared up at his big brother's true ka form. For some reason, the sight did not scare him or even disturb him. It filled him with awe, joy, and pride. In this form, Seto could fly. That had always been the elder Kaiba's deepest desire, to fly with his Blue Eyes. And the wings were beautiful, ethereal, and clearly powerful if the blasts of wind they created that blew back their entire group was anything to go by.

The one thing that did disturb Mokuba was the silence. Not once had his brother's ka form made a sound, not even a grunt of effort or a sigh of breath. His chest did not move, nor did his nostrils flare or his lips part allowing him to breathe. A ka was a purely spiritual being. It had no need to breathe. It had no need for the material, physical world. It had need of one thing and one thing only: its ba.

That was what scared Mokuba. The thought of no longer being needed or even wanted by his big brother, the one thing that he could count on to remain constant and loving in his life suddenly no longer needing or wanting him, leaving him behind, was too terrifying to comprehend. Seto needed Mokuba. Mokuba needed Seto. They needed each other. They could not live without the other. Mokuba could not loose Seto. Not for anything.

"So beautiful," Mr. Bakura murmured. "So wild. So...so powerful."

"Mr. Bakura," J'onn said calmly. "I'm afraid I must ask you to step back."

"Can't you see?" Mr. Bakura asked, eyes sparkled with excitement. "It's...it's real. I've studied it and theorized its existence but it's real. This...this is proof. This is the proof I need."

"Proof for what?" Diana demanded.

"Seto," Seth murmured in hieratic so softly as to be a whisper, "return to me. You have wandered far and seen much. But it is time to come home. It is time to wake from this dream. Return to me, or you will never find rest, you will wander forever in the endless darkness until you fade into nothingness."

He took one last step so he stood chest to chest with his ka. Without breaking eye contact, he turned his hand so it was parallel to their bodied, the only thing separating them from each other. His ka's fingers remained still, just barely touching his palm until he gently pressed his own fingers between his ka's, twining them together. He lifted his other hand and tenderly trailed the pads of his fingers along the sharp jawline up into the soft brown hair, brushing the feathers there.

"Your appearance gives me hope," Seth whispered. "Seeing you like this, it reminds me that I am strong. That we are strong. That we are irrevocably bound to one another." He leaned in close, still holding his ka's gaze with his. His ka mirrored his movements, leaning forward until they were but a hair's breadth apart. "You are mine," Seth whispered, "and I am yours. Return to me, my ka," he breathed.

His ka's eyes softened, its eyelids drooping as if lulled by a some unheard lullaby.

In the outer chambers Ishizu shifted, favoring her injured leg. She lifted her head and saw the beginnings of her Regent's ka returning to its ba. She also saw the man who had shot her with such an unusual weapon standing in the doorway leading to the burial chambers. She also saw what the others did not.

"Pharaoh stop him!" she cried.

Her warning startled the ka who stiffened and turned to the sound of Ishizu's voice almost as if recognizing it. It saw the mortal who dared disturb its ba's resting place, its home, pull something from his pocket and its instincts screamed threat! But before it could act, it was yanked back towards the presence it knew but did not and awareness suddenly faded.

Seth sensed his ka about to strike and pulled it back to him, into him. That short moment of vulnerability before striking had given Seth a small window of opportunity. It was easier and less jarring if both parties merged willingly, but it could be done so long as both had their defenses down. Thankfully, they had already been on the verge of merging when Ishizu distracted them making the forced union less painful but no less sudden.

"No!"

Seth ignored the defiant cry and fell to his knees hugging himself. He gasped as his soul and Kaiba's merged and separated, whirling around each other within Kaiba's body reacquainting themselves and finding their rightful place. He closed his eyes and sank deep into their shared soul room. This had to be dealt with now.

"Mokuba," Yugi called. "Whatever you do, don't leave them alone."

"Count on it," Mokuba said fiercely. He positioned himself directly in between his brother's hunched body and the others.

Yugi narrowed his eyes. "What was the meaning of this?" he demanded. "Why did you do this to him?"

"Do you have any idea how rare it is to see a ka and a ba in their most primal form?" Mr. Bakura said, eyes alight with dangerous glee. "I can think of several houses who would pay a high price for that."

"Price?" Yugi gasped faintly. "You mean...sell a soul?"

"A commodity merely," Mr. Bakura said, waving his hand dismissively. "Just like land, money, oil, water... Each is a commodity, but none are worth fighting for." His eyes focused on Kaiba's still form, like a hunter focused on prey. "There is very little in the universes worth fighting for except more time and something new."

"You're sick," Arrow hissed in disgust.

"I agree," Diana said.

J'onn remained silent, but his eyes were glazed as he focused on this man's thoughts. They were surprisingly orderly, well organized, and cold in an almost scientific way. Everything he said and did was objective and calculating. He truly believed everything he said. He saw Kaiba as something useful.

A ka and ba as two separate entities, independent yet codependent for their very existence was a new concept for him. It intrigued him as it would any scientist who discovered proof of something they always theorized existed but never actually saw. The image of Kaiba as a ka was portrayed prominently in the man's mind as was the sight of Kaiba's body.

Mr. Bakura had already put two and two together and gotten four. If the feathered being with the same face as the human before it was the ka, then that meant the person in the human body was the ba. It was everything he had ever dreamed of. This would not only buy him more time, it could buy him power, entitlement. No, Entitlement. It would make him an Entitled.

"You are not from this world," J'onn said, finally understanding.

"What?" Arrow gasped.

"What do you mean?" Yugi demanded.

"You are not from this universe," J'onn said, narrowing his eyes.

"You think your universe is the only one in existence?" Mr. Bakura -was that even his real name?- asked.

"No," Diana said. "We know it's not."

"Good," Mr. Bakura said. "At least you aren't complete imbeciles." He clasped his hands together in front of him and smiled politely. "Now, I'll ask politely. Hand over you friend there, and I'll be on my way."

"I'm afraid that's not possible," J'onn said.

"Over my dead body," Wonder Woman said.

"That can be amendable," Mr. Bakura said easily, drawing his weapon. It was a gun, but a gun unlike any the group had ever seen before. A canister of orange liquid began glowing eerily accompanied by a high pitched whine.

:Yami,: Yugi said, stepping back in fear.

:I'm ready, aibou,: the Pharaoh whispered in his mind.

"Diana," Yugi said aloud. "Don't let this last longer than a few minutes. Arrow?" The vigilante glanced at Yugi warily from under his hood. "Protect Kaiba."

:Alright,: Yugi said. :I'm ready.:

Without waiting for a reply, Yugi closed his eyes, grasped Yami's soul, and pulled him as close as he could. It reminded him of when Yami used to take over his body back when they still held the Millennium Puzzle. Only instead of allowing Yami to take over, he brought him closer to a level he had only experienced a few times but knew intimately. And then he was no longer. He was no longer Yami. They were now one.

"If you want my cousin," he said with all the power and authority a Pharaoh of Egypt and full Akh rightfully wielded. "Then you'll have to go through me first."

"Seto!" Seth called the moment he appeared in their shared soul room.

The room was dark and filled with long, dark shadows. Seth squinted into the dark corners of the room before movement to right caught his eyes. Sure enough, there was his ka, curled in a fetal position in the far right corner by the trunk. Wide glacial blue eyes were staring directly at him with apprehension.

Seth had never felt so powerful suddenly. It was as if his and Seto's positions had been switched. Seth was now the one with the power to accept or reject and Seto was now in the precarious position of relying on Seth to exist. It was exhilarating and terrifying.

Heaving a deep sigh to calm his nerves, Seth approached his ka, holding Seto's gaze with his own. When he was close enough, he knelt so he was now at eye level with his ka. For a moment, he did not move, simply stared directing into those birdlike eyes. Then he slowly lifted his right hand and held it palm up just as he had in the physical world moments before and waited.

Minutes passed before Seto finally placed his fingers hesitantly on Seth's palm. Repeating his motions from before, Seth turned his hand so it was parallel with his and Seto's chests and entwined their fingers together. This time, however, he went one step further. He squeezed his ka's hand briefly before bringing it up to his chest. The soft, translucent linen of his shawl met his skin but more importantly, he wanted his ka to feel what was beneath his shawl, beneath his skin. The fluttering, reassuring beat of his heart.

He knew the moment his ka felt it. Seto's eyes flickered in confusion and surprise before breaking away from Seth's to focus on where their hands rested. "You feel that," Seth whispered. "Just as you feel the shadow you cast. It is yours just as this," he pressed their twined hands harder to his chest, "is mine."

His ka tilted his head sharply, those hard eyes lifting to meet his once more seeking comprehension. Seth smiled gently.

"You are mine," Seth said. "So this is yours," he said, brushing his thumb over Seto's hand. "And your shadow is mine. We are one and the same, two halves of the same soul. Separate, I am Seth and you are Kaiba Seto. Together we are Set, cousin of Atem, and keeper of the Millennium Rod. I am your ba and you are my ka. You are the Regent of the Shadow Realm and Earthbound Shadow Kingdom."

Something very human flashed in those cold avian eyes.

"Your form reflects mine," Seth continued. "Let me show you."

Seth dropped his barriers and opened himself to his most basic, raw form just like the one Seto currently wore. When he opened his eyes once more, he was hyper aware of the feathers in his hair and at the nape of his neck. Feathers that were both tattoo and real rustled as he reached out and traced the backs of his fingers along Seto's cheek. Seth's arms were covered in soft brown and white speckled feathers. He was more bird than Seto, but more human than most ba could ever be.

"You see now," Seth said, reveling in the shocked gaze of his silent ka. "I am a ba. More importantly, I am your ba. And you are my ka." He leaned forward so he was very much in Seto's personal space and breathed in a voice just barely audible, "My ka."

Seth pressed his cheek to his ka's, nuzzled him tenderly, lovingly. "My ka," he murmured.

The hand pressing against his heart twitched. "Seth," a voice that was his own but not whispered.

"Seto," Seth murmured.

"What..."

"Shhh," Seth said softly. "For now, just return to me."

When his ka finally relaxed in his arms, Seth knew he had won.

"Where am I?" he heard Seto asked, confusion clear in his words.

"In our soul room," Seth replied, pulling his power and influence back until his human traits emerged and his avian form was absorbed back into him. But he did not pull away from the nuzzle.

"That's not what I meant."

Seth sighed. "We are in Set's tomb. Safe."

"Mokuba?" Seto asked in a slightly stronger voice.

"Safe. He is next to us in the waking world."

Seto did not speak for several moments. "What happened to me?"

"You were taken from me," Seth said, instinctively holding his ka tighter, closer. "But you came back." He turned his head to whisper the words into Kaiba's ear. "You came back to me, my ka."

Seto shivered minutely but made no other indication of his feelings. "Who else is here?" he asked instead.

"Yugi, Yami, Arrow, J'onn, and Diana are here with us," Seth said. "Ishizu was here but she... She is wounded I believe."

Seto stiffened. "How?" he demanded coldly.

Seth sighed in regret as he reluctantly leaned back to gaze at his reawakened ka directly. "I am unsure. She was outside of our burial chambers with Carter Hall and Mr. Bakura." Seth's eyes darkened as realized something. "Mr. Bakura recognized you for what you are," he said. "He knew you were a ka."

Seto's brows furrowed in disbelief. "How?"

Seth shook his head. "I do not know. I forced us to merge back into our soul room before you attacked him."

"Attack him?" Seto repeated, bewildered.

Seth nodded. "You are a ka and the duty of a ka whose ba has passed on is to defend the body as best it can until the ba returns from its daily flight under the sun. You were doing just that. You never attacked unless you deemed yourself or Set's corpse in danger."

"Did I hurt anyone?" Seto asked after a moment.

"No," Seth reassured him. "Only stunned-" He stopped speaking abruptly when he felt the Dark and Light suddenly merge into a perfect balance that could only be one thing.

"That..." Seto murmured in shock.

"Atem," Seth confirmed, just as unnerved. "What is going on out there?"

"If we woke up, I think we'd know," Seto said, the familiar snark a welcome relief.

"As you say," Seth said, his lips quitking up in relief. It was nice to have his ka back. "Do you wish to wake as you are or..."

Seto considered a moment before replying. "If Yugi and Yami brought Atem into this, then they had good reason." He looked up to the carving on the column on the Egyptian wall to his right in thought. "Perhaps we should join them."

Seth nodded. "As you say," he said.

Without another word, he leaned close to Seto, closer, as close as he could get until he leaned into his ka. Then he was no longer Seth and his ka was no longer Seto. They were Set. This arrangement could not last long. But hopefully it would not have to.

Set stood from the dark corner of his soul room, closed his eyes and returned to the physical world. The body he currently inhabited did not truly belong to him. If he stayed long in this body, he could potentially destroy it. He prayed to Obelsk such a thing would not happen. He felt as well as heard a deep growl in his soul and Deck -Deck?- which he recognized as his god's and smiled.

Forcing his borrowed legs to move, he stood and lifted his head. A young boy stood next to him, the same boy he remember from the last time he wore this body. He knew this boy's name. Mokuba. This boy was precious. Nothing could happen to him. Nothing.

Such devotion, he thought absently.

Lifting his eyes to take in his surroundings, he felt vaguely ill. This was a the burial chamber of a tomb. Something in his gut told him this was his burial chamber. Just the thought of it made him uncomfortable. Suddenly, a voice he would never be able to forget, a voice that forever haunted his min, echoed in the stone chamber.

"You'll have to go through me first."

Such simple words. But the power behind them was crushing even to him, the authority forcing him to physically fight the urge to fall on one knee and swear his allegiance to this man once more. Biting back the desire, he turned his eyes to the scene unfolding at the entrance of this room and his eyes grew round.

An Amazoness stood shoulder to shoulder with hooded archer -kohai, something deep inside him said possessively- a blue-green skinned humanoid who appeared to be struggling between staring at him and staring at the third person in the room. The only person Set truly cared about.

"'Tem," Set whispered.