Cerberus, formerly known as Rex Crozzo, hummed as he leaned on a tree trunk inside the city of Liyue, the former geo archon was unbothered by the current commotion about his predecessor's 'death'. After all, he had already known about this plan.

"You're quite lazy for someone," the voice of his first friend in Liyue, the best lawyer he has ever known, echoed in the air. Teal-green met with a pair of lazy obsidian orbs. "for someone who witnessed the death of this country's deity," 

"Shut it, Yan," Cerberus said as he stood up, effortlessly keeping his balance as he gently pulled and pinched the lawyer's cheeks. "Besides, I am not really from Liyue." 

"Ow! I know!" Yan Fei said, slapping his hands away and rubbing her cheeks towards the former archon.  

The former archon, master of the Adeptus arts, second only to his predecessor, chuckled as he took out a book from his pouch and hummed, enjoying the difference in height between him and his friend. 

"And I am saving my energy for later," 

"I swear, you picked up a lot of things from Miss Yelan," shaking her head, the advisor gave the young man a smug smile. 

"Is that jealousy I hear, Yan?" Cerberus asked, raising a brow toward his friend who just grinned at him. 

"Nope!" The half-Adeptus said with a grin as the two walked on the streets of Liyue with Cerberus helping Guoba return to Xiangling. 

During the Childe fight

Cerberus hummed as he felt the ancient deity, Osial, rise from its seal while kicking his feet as he sat on the railings beside Zhongli. 

"Well, I'm heading up there, need anything?" The former archon asked his predecessor as he stood up on the railings while stretching lightly. Hearing no reply, the former archon looked at his predecessor who shook his head. 

"Go, while this is not what I expected, having you go there will be enough help for them, after all, while you are my successor, you are not the inheritor of my name, thus this does not interfere with the contract." 

"Okay, then," Zhongli smiled as his successor disappeared in an amber flash as he prepared to interfere should the Qixing and his Adepti fail. "Watch, my reincarnation. Watch your predecessor, the man who sacrificed godhood," 

-------

"Faced with a calamity of such magnitude, we have agreed to put our mutual differences aside for now and unite against this common enemy," Ningguang said to Lumine as she stood side-by-side with the Adepti.

Cerberus smiled as he kept his presence hidden from everyone in the Jade chamber. Sitting on the roof with his spear resting on his shoulder, the former archon watched the light show Ningguang put on. 

Noticing the approaching Fatui soldiers, the young man smirked as his spear morphed into a single-edged greatsword similar to Qrow Branwen's harbinger. Disappearing in an amber flash, the former archon reappeared in front of the portal, effortlessly cutting down several pyro agents and spartan kicking a cryo agent off the platform before chucking his greatsword towards the portal.

"Room for one more?" Cerberus asked as he dodged a pyro agent's attack and kicked him towards a Cicin mage back towards the portal just as he formed an amber circular shield and bashed an electro agent with enough force that almost everyone could hear the agent's equipment and bones break as he was sent flying out of the platform. 

"Cerberus?!" Paimon shouted at the sight of the person that helped them just to look in awe as he formed a bow just to use a spear as an arrow, towards the portal until an explosion was heard from the other side. 

"Oh, hey, Paimon!" The young man greeted as he deflected an agent's knife and broke his arm before doing a jumping-turning side kick that sent the agent to another group. The former archon smiled as he formed a shield and spear before effortlessly combating several Fatui agents with no effort before changing to a double-edged greatsword and using the reach of the blade to take several at once. 

Holding the blade for more control, the former archon used the greatsword like a spear before killing a fetus agent and spraying blood on his cheek before kicking the sword's pommel, launching the agent on the portal while jumping. 

Forming a bow mid-air, the young man pulled the string back just as three arrows formed on it. Letting the string go, amber crystals covered the portals just as he landed on the Jade palace's stone platform while dusting his sleeve nonchalantly. 

Xiao narrowed his eyes at the young man but held his tongue. 

"Yo, Ningguang, nice ass," Cerberus shouted, breaking the tension as most of the mortals looked at him as if he has gone insane, "But to be honest, we can't hold back Osial like this," Cerberus said as he saw the cracks on the amber wall he built to block the portals. 

"That is true, I am sorry for not being able to fight as I once did," Ganyu said, gritting her teeth in frustration as she readied her bow. 

Cerberus rolled his eyes and gently patted Ganyu's head between her horns. 

"Don't worry,"  Cerberus said, catching her attention as the young man removed his head from her head. "I'll help," 

A dull amber glow appeared from Cerberus' eyes as he reached for his pouches. 

"Human, who are you?" Cloud retainer asked, narrowing her eyes at Cerberus and at the sheer power that escaped the mortal. Countless sigils containing Adeptal power soared and danced around him. All of those in the Jade Palace could only watch in awe at the sheer amount of power radiating off the young man. 

Spreading his hand out with a bright grin, the former archon felt his Adeptus art take its effect. 

"My former name means emperor," Cerberus announced, power resonating from his voice alone as the Fatui, dozens of them, flooded the portal. "I sit on a throne in front of my foes, never retreating or succumbing to my fears. My shield will fend off the harm going your way and heal your wounds! Fight to the bitter end! Fight till the last drop of blood leaves your body! This is how me and my family have fought our ancient foe for millennia!" Power and an amber glow surrounded the Milelith and those on the ground as the young man looked at Osial.

"Those who seek to bring harm in front of my gaze shall Fall," The young man whispered as soon, as intense pressure bared down on the Fatui soldiers, causing the weak-willed to pass out while making many kneel in a cold sweat. 

Silently, Cerberus observed as he let his powers flow, strengthening his allies before digging and opening another pouch filled with Sigils. 

"Adeptus Art: Melammu Dinggir!" 36 cannons similar to the Guizhong Ballistae formed in a circular pattern around the Jade Palace as Geo energy flowed towards them, releasing blasts of concentrated power, rendering the salvo that the overlord of the Vortex sent as a stone tablet formed on Cerberus' hand. a bead of sweat fell from the young man's head as symbols erupted from the stone tablet as salvo upon salvo of Geo energy battered Osial. 

------

After the battle,

"So, what's the deal with Cerberus?" Paimon asked Zhongli. 

"Cerberus is my successor. The second geo Archon," Zhongli said with a proud smile. "That would be the case if he hasn't given his godhood and Gnosis. That caused me to be reincarnated in a sense," Zhongli said, remembering the memories he has seen of his successor from Cerberus' journey to discover himself and relying on his creativity and skill that allowed him to fight and win againt beings similar to Archons despite not being as capable compared to his successor that became the strongest in his universe, Y/N. 

"Woah! Then, shouldn't he be not allowed to help Liyue?" Lumine asked, looking at the Archon who smiled at the sight of Cerberus having his ear pulled and dragged by Yan Fei. 

"No, while it is true that Rex Lapis can not interfere during the trial I have set, Cerberus never inherited my title. In fact, his title and name were given to him by a dear friend of his," 

"What's his title?" Paimon asked, looking at Zhongli. 

"Rex Gaius, the joyful lord of the earth," Zhongli replied as he watched how his former successor mended the leylines,

================================================================================

Omake: Cerberus in Warhammer 40k

Cerberus blinked as he looked at the skeleton on top of a golden throne as he sat on his amber plastic chair comfortably. 

"Who the fuck are you?" Cerberus asked as he looked at the skeleton on the golden throne, ignoring the gasps of those around him. 

"Ah, Sir Rex Crozzo," a telepathic voice appeared on his head.

"Wait!" Cerberus shouted as he looked around, "You, machine guy. Give me a text-to-speech device," Hearing nothing, the former archon scowled as he sent a pulse on the ground and reappeared in an amber flash behind the throne and plugged something into it. 

"FUCKING FINALLY," the robotic voice came from the emperor of mankind. "WHY DID IT TAKE ME, SUMMONING AN ANCIENT HUMAN FROM THE SECOND MILLENIUM THAT SEALED HIMSELF TO STOP AN ANCIENT EVIL TO FINALLY CONNECT A FUCKING TEXT-TO-SPEECH INSTALLED ON MY THRONE," 

==============================================================================

Omake: 

"Are you serious?" Cerberus said as he had just finished eradicating the 20th highly corrupt Ecclesiarch church. 

The former archon stared at a familiar young woman surrounded by the light of the emperor of mankind, dressed in white and purple armor belonging to the sisters of battle that mixed well with her hair and eyes. 

"Ah, lord Crozzo, it seems that you have finally met her. May I introduce you, the living Saint, Kiana Kaslana," 

The former archon whimpered as he saw Kiana fly towards him and hugged him hard. 

"Rex! I missed you!" Kiana shouted, holding the former archon in her embrace. 

==========================================================================

Omake: Harmonious earth IF

Rex Crozzo opened his eyes as a bright light filled his vision. The sight of a futuristic wall filled his sight as he looked around. Feeling a familiar weight stopping him from his movements, the young man smiled at the sight of the sleeping form of his childhood friend, who was dressed in her Herrscher of Finality attire, the former archon smiled as he removed his archon cloak, leaving him in his suit similar to his great-granduncle, Otto Apocalypse but with inverted colors. 

"Kiana, wake up," Rex said, shaking his childhood friend gently while Kiana pouted and hugged his hand tighter. 

"Five more minutes, Rex," Kiana said with a pout as she opened her eyes and looked pleadingly at him. 

"Fine," Rex said as he remained seated on the cool metallic floor with Kiana curled around his arm. 

-----------------

"Mr. Welt!" Kiana cried out as she ran ahead of Rex and towards the older man with Rex's coat around her. 

"Kiana Kaslana?! How are you?!" Welt asked in shock as she looked at one of the two that sealed the Honkai away. "Then, that means," 

"Hey, Uncle Welt..." Rex greeted with a smile as Welt hugged his adoptive nephew and surrogate son tightly along with Kiana. 

=============================================================================

"No! Rex is mine! Get your own!" Kiana shouted, hugging the archon tightly as she glared at Stelle, who hugged his other side. "You too, Bratnya! I saw you look at him!" 

Bronya Rand blushed as she heard Kiana while Seele just chuckled. 

"Especially you, Seele! I know what kind of girls Rex like and you're one of them!" 

Seele and Rex both burnt red as Kiana and Stelle played tug of war with the Archon.

-=============================================================================

Rex gently let Kiana rest her head on his lap as he checked the bloody plug on her nose......

"Rex... I can die in peace now..." Kiana whispered with a perverted grin. "MILF Mei-Sempai," Kiana giggled pervertedly as the archon sighed.