Heroic Spirit Deck in Yu-Gi-Oh!

"Please, I beg you—don't fight anymore!"
"You are…?" Hoshino Alter froze, the card in her hand hovering midair, just one step away from finishing Diva, as the girl Sera suddenly rushed forward and stood in her way.
On the verge of tears, Sera clung tightly to the pale-faced Diva.
"Please, Hoshino! My brother… he's only trapped in sorrow because of losing Lord Shadi!"
"Brother?" Hoshino Alter raised a brow, taking in Sera's strange attire.
"Aimagi, you actually have such a cute little sister?"
"Get out of the way, Sera!" Diva weakly pushed her aside. Despite the severe blood loss from his thigh wound, he still trembled as he raised the card in his hand.
"I haven't lost yet… The Cubic power Lord Shadi entrusted to me—I must use it for revenge!"
"Onii-chan, if you keep going, you'll die!" Sera snatched the card away, desperately trying to stop him.
"I already lost Lord Shadi. I don't want to lose you too!"
"Enough." Hoshino Alter lowered the card in her hand. With Sera's interruption, she no longer had the heart to continue.
"In your condition, there's no way you can defeat me. Besides, if something happened to a student on graduation day, from the same school… I'd never forgive myself."
Seeing Diva's face drained of all color, his lips darkening, Yugi panicked.
"Wait—Aimagi's condition looks bad! If we don't stop the bleeding soon, his life's in danger!"
Anzu immediately sprang into action.
"Hold on, I'll get the nurse!"
Diva stared in shock, unable to comprehend why Hoshino had stopped. Before the duel began, he had fully intended to eliminate her. Yet now, she was stopping because he was losing too much blood.
"Hoshino… are you pitying me? If so, there's no need. I long ago accepted the resolve of avenging Lord Shadi. Or is the so-called 'Duel King' really just a saint, sparing even an enemy who sought her death?"
Hoshino Alter shook her head.
"A duelist's soul never lies. If your hatred and rage truly sought my death, you wouldn't have needed to hurt yourself just to force more power out of your Cubic beast."
"Don't joke with me! To repay Lord Shadi—that's my lifelong goal! And now you're saying my anger isn't enough?!"
His strength finally gave out, and Diva collapsed onto the ground. Around them, the dimensional field sustained by the cube slowly faded away.
"No." Hoshino Alter crouched down slightly, smiling at the fallen boy.
"I never met Shadi myself, but through your feelings, I can tell he must have been a gentle man. Someone that kind—don't you think he would never want hatred planted in your heart, even after he's gone?"
"That's right, Onii-chan!" Sera threw herself into Diva's arms.
"Lord Shadi never wanted you to avenge him. He never hated the Pharaoh or Hoshino. He only gave you the Cubic because he hoped you'd find your own path—your own purpose beyond him!"
"Lord Shadi… that's what he wished?" Diva's mind drifted back to Shadi's final words. Looking up at Hoshino Alter's smile, he fell silent.
"The nurse is here!"
The crowd of students quickly parted. Dressed in a white coat, Nurse Emi Ayukawa—known throughout the school as a glamorous, beautiful older-sister type—hurried over. She was admired by both students and teachers alike.
But when she saw the cross embedded in Diva's thigh, blood still seeping and staining the ground red, her expression turned grave.
"What on earth happened, Aimagi?! How could you be this badly injured?"
Her tone was half scolding, but also filled with genuine concern. She opened her medical kit, performing only basic treatment on-site before preparing to take him to the infirmary.
Scratching his head, Diva slipped back into his harmless act, explaining with a sheepish grin:
"I, uh… confessed at graduation and got rejected by Hoshino-senpai, so I lost my head and did something stupid. Sorry, sensei~"
His performance was flawless. His ability to switch faces so quickly even left Hoshino herself impressed.
"You young people," Ayukawa sighed, "always acting on impulse. Even if you get rejected, you can always come to sensei for comfort, you know?"
Hoshino Alter interjected, "Sensei, that sounded… dangerously inappropriate just now."
"Fufu, I may not be as pure and cute as you JK girls, but I won't lose in terms of charm~"
After bandaging his wound, she gave Diva a light tap of admonishment.
"Alright, Aimagi! To the infirmary, where sensei will take good care of you. You two boys, help carry him."
"I'll do it!"
"Me too!"
The call drew an eager crowd of male students in an instant. In a heartbeat, Diva became a prize, carried off by a group of burly classmates.
Watching him disappear in a swarm of volunteers, Hoshino Alter smiled toward Hoshino within the golden pyramid.
"That should count as a clean resolution, right, aibo?"
["I still don't like that dimensional cube of his… but he himself isn't a bad person. I don't think he'll cause any more trouble."]
"Thank you, Chiyuki Hoshino, for sparing my brother."
Sera, timid and small, bowed her head gratefully, relieved that Diva was safe.
"You're Sera, right? For you to muster the courage to step in front of him like that… it shows how much you care about your brother."
The adorable girl stirred Hoshino Alter's protective instincts, and she reached out to pat Sera's head.
But the next moment, her hand passed right through Sera's body—like touching a hologram projection, with no substance at all.
"What…?" Hoshino Alter stared at her own hand in bewilderment.
A soft, familiar voice whispered in her ear—it was the Evil God.
"Girl… this one is closer to a spirit than a human."
Sera shook her head.
"No, I'm human."
"You… can hear me?" For a brief moment, surprise flickered in the Evil God's eyes. As a spirit given form, no human besides Hoshino should have been able to sense her.
"The power of the dimensional cube sent my consciousness into the gap between this dimension and the higher one," Sera explained.
"I can't move forward, nor return. So I exist here only in a spirit-like form."
"Trapped between dimensions… how pitiful. But Sera, what exactly is this cube? Why does it hold such power?"
"The Millennium Item. That's how Lord Shadi described it. It can absorb the powers of the other Items, and serves as a tool to lead humans toward a higher dimension."
Hoshino Alter arched a brow.
"The eighth Millennium Item? …So it really is common knowledge there are more than seven. But if it can lead humanity to a higher dimension, why are you trapped in the rift?"
"Because I failed. To ascend, one must be chosen. Lord Shadi once told my brother and me about the parallel world. Only the strongest duelists who can traverse parallel worlds may have their consciousness elevated into the higher dimension."
From within the pyramid, Hoshino's voice echoed:
"Duelists who can cross parallel worlds… that's just me and Jaden, isn't it?"
When it came to crossing between parallel worlds, the first thing Hoshino thought of was the time she had traveled ten years into an alternate world. Similarly, Jaden had crossed over from ten years later in another timeline into her own.
"But even so, I really don't want to be dragged into some so-called higher dimension out of nowhere."
Just the thought of the grotesque forms of the "Cubic Monsters" made Hoshino Alter shiver. If the creatures in that higher-dimensional space all looked like those things, then having one's consciousness "ascend" there would be a fate crueler than death.
Rubbing her chin, Hoshino Alter came to a conclusion.
"Come to think of it, whether or not the consciousness can actually reach a higher dimension, that Cube is nothing but a dangerous artifact."
["Speaking of which, isn't it about time we swapped back? Can't you be a little more self-aware—like Atem, who immediately gave the body back once a duel was over?"]
"No way!" Hoshino Alter flatly refused. "It's rare that I get to come out and look around! At least let me stay until after dinner. Otherwise, I'll feel like nothing more than a disposable tool!"
When exactly did you get the idea you weren't a tool?
Delighted with her long-awaited chance to experience the outside world, Hoshino Alter was in high spirits. Since the school was holding its graduation ceremony today, there were no classes, meaning she could spend the entire day having fun before returning.
Unable to contain her excitement, she spun around and declared:
"My dearest friends, as a celebration for graduation, why don't we all relax and enjoy ourselves at the shopping district~?"
Yugi responded with subtle hesitation: "If there are no classes today, going out isn't a bad idea… But Hoshino, are you really okay with that?"
"Me? Why wouldn't I be okay with going out to have some fun?"
Jonouchi reminded her: "Hey, hey, Hoshino, don't tell me you forgot—tomorrow's the duel you promised Kaiba! Didn't you say that duel would decide the course of your future?"
Bakura nodded in agreement. "Yeah, and if your opponent is Kaiba, it won't be an easy duel. Shouldn't you be using today's free time to adjust your deck and your focus?"
"Ohhh, that duel with Kaiba!"
Hoshino Alter suddenly remembered—not that she had truly forgotten, but it wasn't her who had promised Kaiba. When the time came, it would be Hoshino standing on the field. All she had to do was handle the background music and cheer from the sidelines.
"Don't worry, it's totally fine. We're just talking about Kaiba, after all. No need for me to prepare at all~ (Since aibo will be the one dueling anyway.)" Waving her hand dismissively, Hoshino Alter mocked him across the distance.
"So, aibo, you just focus on adjusting the deck inside the Pyramid of Light. Today's fun will be handled by yours truly~"
Jonouchi, fired up by her confidence, chimed in: "That's right! It's only Kaiba, what's there to worry about? Then let's go make the most of today! Let's celebrate what little time we have left of high school!"
"That's the spirit, Jonouchi! First, let's go eat some yakiniku until we burst!"
Rubbing her flat stomach, Hoshino Alter knew without a doubt that Hoshino had skipped breakfast again this morning to rush to school. Maybe the reason her figure had slimmed down over the last two years was because of such horribly irregular eating habits.
Yugi exchanged a glance with Anzu, forcing a faint smile. "I just hope everything really will be fine. Let's pray Hoshino won't let her guard down when the time comes..."
—Inside the Pyramid of Light—
Seated at a desk in the room, Hoshino spread her deck of cards across the tabletop.
Even she didn't know how Hoshino Alter managed to conjure up all these realistic furnishings inside this void-like space of consciousness—the closet, the large bed, everything was here. In fact, it didn't feel any worse than her own shabby storage-room lodgings.
"The duel with Kaiba, huh… Feels like I haven't seen him much lately. Did he secretly go to Pegasus to print cards?"
While gazing at the cards spread before her, Hoshino pondered tactics. Even though strategy usually depended on knowing the opponent's deck, Kaiba's core would never change. No matter how he rebuilt his deck, it would always revolve around his three Blue-Eyes.
"Speaking of printing cards, I'm not exactly behind on that front myself!"
Over the past two years, since the end of the Seventh Singularity, new card pools had opened from the four pseudo-singularities: Epic of Remnant – Shinjuku, Agartha, Shimosa, and Salem. Through relentless effort, Hoshino had managed to collect nearly every card—save for a few special Servants.
And since the kids at Game Shop weren't enough for her ruthless "harvesting," she had to expand her sights to other toy stores across Domino City.
Because of her merciless methods, she had even earned the title of "Toy Shop Reaper," a name on par with Hakutaku's former title of "Shop Destroyer."
"Hey, Master, for this duel—can I get a turn?"
Sneaking out from the spread of cards, Abby plopped herself down on Hoshino's lap. In the space of the Pyramid of Light, even spirits could freely materialize.
"If you want to join, Abby, that would mean riding a Duel Runner to the Duel…"
Hoshino looked troubled. Even after two years of effort, she still hadn't managed to get a motorcycle license.