Arthur's tiny face grew serious—it was time to test what he had gained.
"[Overlord], open the Material Library. Let me see how much I've collected."
"Affirmative. Material Library accessed. The host has extracted a total of sixty-two types of C-grade materials and two types of C+ grade materials. All are available for use or synthesis."
"Sixty-four types in total? Not bad… not bad at all."
Arthur was genuinely surprised by how many materials he'd gathered. Certain resources, like [Magic Crystal Stone] and [Fiboku Herb], had been especially abundant in this cave. They were practically everywhere, so he harvested them without hesitation—even scraping the crystal-covered walls clean in the process.
"These will definitely come in handy later."
"[Great Overlord], can I extract materials directly for use? Also, explain your second function, [Synthetic Creation]."
"Confirmed. All stored materials may be retrieved at the host's discretion."
"As for [Synthetic Creation]: this function allows the combination of various materials to synthesize items—or even living entities—imbued with the properties of the selected materials. Note: success rate varies depending on compatibility."
"Synthesis can fail? And you're saying… I can create living beings?"
"Affirmative. With appropriate materials that possess special attributes, lifeforms can be synthesized. The strength and abilities of the resulting entity are determined by the input materials. Note: synthesized creatures are under host's absolute control."
Arthur blinked in disbelief. The little wings on his back fluttered involuntarily.
"Creating loyal subordinates from scratch… Could I even synthesize a Demon Lord someday?"
He chuckled quietly at the thought but quickly reminded himself—there had to be restrictions and prerequisites for such a feat.
"Well, no harm in experimenting. This [Synthetic Creation] might surprise me."
He turned back to the Material Library, overwhelmed for a moment by the variety. Then he decided to go with his gut.
"Forget it—let's try a random mix first."
He selected a few items and issued a command:
"[Overlord], synthesize the materials I've chosen."
"Understood." The voice remained emotionless as ever.
"Selected: C-grade [Spider Eye] ×2, C-grade [Poisonous Bun] ×1, C-grade [Sticky Web] ×2. Beginning synthesis…"
A pause followed.
"Synthesis… failed. Compensation: host's magicule limit increased by +3."
"Eh? It failed?"
Arthur blinked, then grinned. "But it raised my magicule capacity? That's not a waste at all!"
Encouraged, he browsed through his stash again. This time, he picked two specific materials—ones he had in abundance.
"[Overlord], synthesize these next two."
After a short delay, the system responded:
"Synthesis successful! The host has obtained: [Magic Potion] ×1."
"[Magic Potion]: Created from [Magic Crystal Stone] and [Fiboku Herb]. Rapidly restores magicules and stamina."
"Now that's a win."
Arthur's wings fluttered in excitement. He knew that Rimuru had once used Fiboku Herb to create a high-concentration recovery potion—one that restored even grievous injuries and magicules alike. This was a similar concept, and he was thrilled.
He summoned the potion and downed it without hesitation.
After all, as a spirit without a physical body, he didn't need to worry about toxicity or side effects.
The potion was housed in a small, translucent blue crystal vial. The liquid inside shimmered with a kaleidoscope of colors—elegant and potent.
He couldn't measure stamina recovery, but the surge of magicules rushing through him was immediate and powerful.
"I feel like I could take on ten slimes right now!"
…
Just as he basked in his newfound strength, something shot across the underground river in front of him. It dashed across the water at an absurd speed, sending up massive splashes.
It zipped past Arthur with a gleeful laugh, splattering his face with water.
"La~ la~ I'm a free slime~ la la la~!"
A cheerful voice echoed in his ears as the mysterious figure bounced away.
Arthur stood there, drenched, stunned—and mildly offended.
Arthur's face twisted in annoyance. He had just consumed a large dose of magic-restoring medicine, and now his body was brimming with excess magicules — but no way to vent them.
Wasn't this… the perfect moment for someone to stumble into his path?
Just then, something came skimming across the surface of the lake.
A slime?
Arthur blinked. He'd seen it clearly — a blue, jiggly slime was coasting across the water.
No way… I met Rimuru this early?
There it was — bouncing along the surface, splashing water everywhere, and even humming a tune like it didn't have a care in the world.
Arthur focused. He could sense Rimuru's magicules. They weren't especially strong right now — maybe just about C+ rank. In fact, Arthur felt more powerful at the moment, thanks to the freshly restored magic in his body.
The slime suddenly halted mid-skid and pivoted sharply, clearly sensing Arthur's presence.
"Great Sage, am I hallucinating? I think I just saw… an elf?" Rimuru asked aloud, voice filled with curiosity and excitement.
The slime bounded over with cheerful energy, then stopped a few feet away. Upon seeing Arthur clearly, its body quivered in surprise and delight.
"Whoa! It really is an elf! A real elf!" Rimuru's body wobbled excitedly, forming something close to a smile on his gelatinous surface.
Arthur, still hovering slightly above the ground in his spirit form, was caught off guard. He hadn't expected to meet the protagonist this way — after all, he was a reincarnator too.
Suddenly, a warning rang out in his mind.
"Alert: An unknown analytical skill is attempting to assess the host's composition."
Arthur smirked. Of course. That had to be Rimuru's infamous skill — Great Sage.
"[Overlord]," he commanded mentally, "block any sensitive information, but allow general analysis."
"Acknowledged."
He remained calm, arms crossed, watching the curious slime.
Great Sage: Report. Analysis complete. Target is an elf. Phenomenon: Lacks physical manifestation — reason unknown. Estimated strength: B+ rank. Hostility: None.
Additional Note: Please cease inappropriate thoughts. Target confirmed to be male.
Arthur raised an eyebrow. Clearly, even Great Sage was embarrassed by Rimuru's assumptions.
"What?!" Rimuru exclaimed. "This cute little elf is… a guy?!"
There was a beat of silence. The slime's form slightly trembled. Across from it, Arthur's expression darkened.
"...What did you just say?"
They stared at each other.
"…Uh oh."
"Damn you!" Arthur snapped, lifting one glowing foot. With all his magicule-infused might, he stomped down—
SMACK!
The slime shot through the air like a comet, trailing sparkles as it flew.
"Ahhh! Wait! Cute elf lady—no, little bro—wait, big bro—AHH—dad?!"
With a mighty thud, Rimuru crashed into a patch of Fiboku herbs across the field, carving a clean trench through the underbrush.
Arthur snorted. "Hmph."