A Battle....Already!!!

Rimuru smirked as he watched Veldora stretching and flexing after centuries of being sealed. An idea sparked in his mind, and he couldn't resist. "Yo, Veldora," Rimuru called out. "How about we spar a little? After being sealed for so long, I bet you're itching for some action. Plus, you're probably rusty."

Veldora's eyes narrowed as he straightened, his confident smirk growing wider. "Rusty? Me? Nonsense! I'm the great Veldora, the Storm Dragon! I'm as mighty as ever!" He struck yet another exaggerated pose, his cape billowing dramatically, though there was no wind.

"Prove it," Rimuru taunted with a grin.

Veldora paused, stroking his chin in mock thought. "Hmmm, sparring, huh? I suppose I could entertain you with a glimpse of my might."

Rimuru clapped his hands together. "Great! Let's do this. Diablo!"

In an instant, Diablo appeared, bowing gracefully before Rimuru. "Yes, my master. What do you require of me?"

"I need you to help reinforce a barrier. Things are about to get… intense."

Diablo's crimson eyes gleamed with excitement, his lips curving into a small smile. "Ah, witnessing my lord's unmatched prowess firsthand is a blessing I did not expect today. Consider it done."

Veldora crossed his arms. "Hmph. No need for so many barriers. My power alone would suffice!"

Rimuru rolled his eyes. "Oi, don't get cocky, old man. You don't even know how much stronger I've gotten."

With that, Veldora raised his hand and created a massive barrier of swirling storm energy, its presence crackling with electricity. Rimuru layered his own barrier on top, glowing a brilliant blue, while Diablo added a third barrier, dark and ominous, to ensure their fight wouldn't destroy the entire cave—or the Jura Forest.

As they stepped into position, Veldora couldn't resist striking yet another heroic pose. "Prepare yourself, Rimuru! I won't hold back!"

Rimuru rubbed his temple, shaking his head. "Raphael, analyze all of his movements and prepare to utilize Omni Evolution to its fullest potential. Let's see what this Ultimate Skill can really do."

Raphael's calm voice echoed.

<>

Diablo stood just outside the barrier, his eyes locked on the two combatants. "Ah, to witness such a glorious battle… My master truly graces me with his magnificence," he muttered, mesmerized.

Treyni's voice whispered from her spiritual form, watching from afar. "They're really going at it, aren't they?"

Diablo gave the signal. "Begin!"

In an instant, both combatants disappeared. A shockwave erupted as their first clash resounded through the cave. Veldora had lunged forward with a clawed hand, shrouded in storm energy, but Rimuru parried with a glowing sword crafted from his magicules.

The air hummed with tension as their blows exchanged with lightning speed. Veldora's sheer physical power forced Rimuru back slightly, but Rimuru countered with a spiraling energy slash that tore through the air, causing Veldora to dodge with a swift leap.

"Not bad," Veldora admitted with a grin. "But can you handle this?"

He raised his hand, summoning a massive vortex of wind and lightning. "Storm Nova!"

The vortex barreled toward Rimuru with terrifying speed, but Raphael had already calculated its trajectory. <>

"Good idea!" Rimuru responded, raising his hand. "Absolute Zero!" A burst of icy energy collided with the vortex, freezing it solid before it shattered into harmless fragments.

Ramping Up the Intensity

The battle intensified as Rimuru and Veldora moved faster than the eye could track, their blows creating shockwaves that made even the reinforced barriers tremble. Rimuru's Omni Evolution continuously analyzed Veldora's attacks, allowing him to adapt mid-battle.

"Impressive!" Veldora roared, blocking a series of precise sword strikes. "You've been holding back all this time, haven't you?"

Rimuru smirked. "I learned from the best… although I think I'm starting to surpass him."

"Big words for a slime!" Veldora shot back, channeling his Ultimate Skill, Faust, Lord of Investigation. The air around him shimmered as probabilities shifted in his favor. He dodged a perfectly aimed strike by mere millimeters, countering with a massive punch infused with storm energy.

Rimuru blocked with his sword, but the force sent him skidding back. "Tch, probability manipulation? That's just cheating!"

"All's fair in battle!" Veldora laughed.

Unleashing Ultimate Skills

"Fine, let's kick this up a notch!" Rimuru declared, activating Veldora. In a shocking twist, he unleashed a scaled-down version of Storm Nova right back at Veldora.

The dragon's eyes widened in surprise. "You're using my own skills against me?! Oh, this is going to be fun!"

The two continued exchanging devastating blows. Rimuru's sword now radiated with magicule energy, each strike leaving trails of destruction. Veldora countered with storm-infused punches and claw swipes that tore through the air like thunder.

Despite Veldora's overwhelming power, Rimuru's Omni Evolution began to shine. With every blow, Rimuru grew faster, stronger, and more precise, adapting to Veldora's attacks as if learning them in real time.

"You're holding back, Veldora!" Rimuru taunted, dodging a spiraling lightning strike. "Did all that time in the seal make you soft?"

"Soft?!" Veldora's aura exploded outward, filling the cave with raw power. "I'll show you soft!"

For five hours, the battle raged on, each of them unleashing their full strength. The cave trembled, the barriers flickered, and Diablo remained frozen in awe.

"This… This is art," Diablo whispered, not daring to blink.

Finally, with one last explosive clash, they both stopped, breathing heavily but smiling. Veldora's muscles glistened as he flexed. "Not bad, Rimuru. Not bad at all."

Rimuru sheathed his sword, a satisfied grin on his face. "You're not half bad yourself, old man. This was… enlightening."

Veldora laughed heartily. "Hahaha! I knew you were something special. You've earned my respect, Rimuru!"

The two shook hands, their bond stronger than ever. Rimuru's goal of testing Omni Evolution was a resounding success, and even Veldora acknowledged the growth Rimuru had achieved.

As they exited the cave together, Diablo bowed deeply. "Master Rimuru… that was the most magnificent display of power I have ever witnessed."

"Stop being so dramatic," Rimuru said, brushing him off. But deep down, he couldn't help but feel proud.

This sparring match was only the beginning of their adventures together, and both knew that greater challenges awaited them in the future.