Megumin had an eager smile on her face as she lifted her staff high. "Call down the fires of heaven and shake the very earth! Exppppllllllloooossssion!"

Magical circles appeared an instant before a massive explosion tore the ground apart. A peaceful meadow was instantly transformed into a smoldering and blackened crater. In the next moment a now limp Megumin collapsed on the ground and let out a satisfied sigh. Grinning, she turned her head slightly to the side to peer up at the person next to her.

"What do you think?"

Kazuma shrugged. "It's a six."

"What?!" She cried in outrage. "That was definitely a nine! An eight at the very, very least!"

Kazuma shook his head. "That's nowhere near your best work. I'll call it a six point five, but that's as high as I'll go."

She muttered something under her breath but didn't say anything as Kazuma loaded her onto his back to begin the long trek home. On the days they weren't looking for jobs he would bring her out somewhere a few miles from Axel and let her cast explosion magic. Kazuma thought it a huge waste of his time, but it kept the little pyromaniac satisfied. (He'd learned that a frustrated explosion loli could be a dangerous thing.)

As he was shifting her on his back, he eyed the still smoking crater.

"Hey, how deep is that thing?"

"Deep?" Megumin blinked and took a second look at her most recent creation. "I don't know. Twenty feet I guess?"

"Twenty feet, huh? What's the deepest one you ever made?"

She paused to consider. "Uh, forty, maybe fifty."

"Oh… I see. Heh," he chuckled. "Well, let's head back."

"Hey! What was that?"

"What was what?"

"That snort of derision!"

"What are you talking about?"

"Just now! You made a derisive snort! I've heard those plenty and know what they sound like!"

"You're imagining things. That was a chuckle, not a snort."

She narrowed her eyes. "Then why were you chuckling?"

"Well, if you really need to know, I overheard a dwarf bragging to some human miners the other day. Apparently, the deepest man-made mines only go down about three miles. But the dwarf boasted that some of theirs went down eighteen, so deep the rocks are hot enough to bake bread."

"I believe it. Everyone knows dwarves specialize in mining. It only make sense they'd have the deepest mines in the world. I don't see how that's got anything to do with me though."

"Oh, well I was thinking that maybe you could match that using your explosion magic. I mean if you could it would be incredibly useful to miners everywhere. But obviously there's just no way that could ever work." He laughed and started walking.

"What do you mean?!" Megumin demanded. "I absolutely could! I'm the greatest Crimson Demon mage in the whole world and Explosion is the greatest spell in the whole world! Going that deep into the ground would be easy for me!"

"Sure, it would, Megumin. Sure, it would," Kazuma made a certain sound.

"Hey! That was definitely a derisive snort just now!"

"If you say so."

"You don't believe me! You don't think I could do it!"

"What? Noooooo, I totally do. I'm just wondering how you'd manage it though if the deepest crater you've ever made is only fifty feet."

"The answer's obvious! I'll just keep deepening the same crater by recasting explosion on it until I get it deeper than any stupid dwarf could ever manage!"

He turned his head to look at her. "Megumin, that would take years. You'd have to cast the spell hundreds of times, maybe even thousands in the exact same spot. Wouldn't that be boring for you?"

"Absolutely not! There's no way casting explosion magic could ever bore me!"

"If you say so," he sounded and looked doubtful.

"Grrrrr, I'll show you! From now on whenever I have a free day, we're coming straight here for me to cast my spell! I won't use it anywhere else until I crack the world!"

"Fine, fine," he muttered. "If that's what you want."

XXX

Two weeks later…

Megumin was back at his mansion recovering from her latest explosion casting. Kazuma was at the guild hall enjoying an ale and the look of awe and near worship in Luna's eyes.

"You actually did it! You got Megumin to stop casting explosion spells all over the place and ruining the landscape."

He grinned and sipped his ale. "I told you I could."

"But how? How did you manage it?!"

He shrugged. "Some people just can't turn down a dare."

"What? What does that mean?"

Kazuma just smiled and refused to explain.

He then went around collecting about two million eris from the many adventurers who'd bet against him.