The knock came at the crack of dawn. Aaron and Mark had spent most of their night sparring and meditating in the small room they were given, away from the rest of the group.

Mark gave no indication that he thought anything of their accommodations, but Aaron knew better than to trust the wily King. He was certain they were being watched somehow, but he couldn't prove it, even after using chi breathing to sense around them.

"The king is waiting for you at the entrance to the crystal catacombs. You're to come at once."

The guardsman was taller and thicker than any other soldier they'd met before, and he carried himself with a confidence that commanded attention. He had a thick beard, and Aaron had no doubt he was a formidable bender.

Aaron nodded and gestured at Mark, who had switched to his oversized armour. He proudly wore one of the two batons on his hips. Aaron was in full armour too, with both blades sheathed by his waist.

They walked in silence, following the guard down a series of winding steps lit by gemmanites as lanterns.

"Any tips for the tests?" Mark asked the guard.

Aaron expected a scoff or chuckle from the guard, but the man surprised him by leaning in and whispering.

"Nothing that'll help you if you're not both ready. But, if I had to say something, it'd be that the first answer is always the wrong answer with the King."

Aaron frowned at the answer, confirming everything he'd suspected, but Mark didn't look any less stressed.

"Chin up," Aaron said, nudging Mark, but he seemed even more stressed. "You've fought firebenders and lived to tell the story. I'm sure you'll be fine."

Aaron nudged Mark, but he didn't seem any more relaxed.

"You did most of the fighting on both occasions, but…yeah, I guess you're right," he said.

"He and the rest of your team are right in," the guardsman spoke up again as they approached a doorway that led into a large chamber. Before they left the guard, though, Aaron asked for the burly guard's name.

"Sato," he said. "And I hope you impress the King. It'd be nice to have a new face around here."

"You're here, good, good," Bumi said with widespread arms as he laid eyes on them. "I have three small tests prepared, and you have to pass all three if you want to get my attention."

"Don't we have it already?" Mark said with an awkward laugh. Bumi laughed too.

"But you need to impress me to keep it." He wagged his fingers.

"What if we fail a single test?" Aaron asked. "Would you still take him?"

"I'm sure you won't," Bumi waved. "You're a trained Airbender, skilled enough to teach a student from a different Nation. You'll do just fine."

Aaron's lips thinned to a fine line. "Then I suppose we should get started then."

"Splendid!" Bumi rubbed his hands together. "The first challenge is fairly simple," he said, gesturing to the cave behind him. They stood on a balcony that dipped low with a long staircase into a crystal chamber with masses of colourful crystals that caught fire light and refracted deep colours.

Aaron could hear a waterfall in the distance, and the air was thick with moisture.

Stolen novel; please report.

"Hidden somewhere in this cave is the key to my pantry. One of my cooks seemed to have misplaced it when he came down here to harvest rock candy for a dish he was making," Bumi said with a wan voice. "Without it, I'm afraid we might not get breakfast at all…"

"Oh no," Sokka gasped in horror, and Katara, who sat beside him, elbowed him in response.

"Ow…" he grumbled. "I just said what we were all thinking. I was looking forward to breakfast."

"Don't listen to Sokka guys, I know you can do it," she said.

"Yeah," Aang chimed in. "You're both great benders, you just have to show Bumi."

"Thanks for the vote of confidence," Mark said.

—

"What sneaky trick do you think the King is up to?" Mark asked as they looked behind the twentieth crystal cluster. They'd been searching for nearly 10 minutes now, but they'd spotted no tracks or anything out of the usual… not that the crystal cave itself was not peculiar.

"He probably wants to test our sensory skills," Aaron concluded. "The Cave is too big for us to search in an hour without any hints or help. We haven't checked the water yet, but that might be another waste of time."

"I say it's not. It's a bit obvious, but it's like a trickster to hide the key in the most obvious place." Mark sighed. "Whether or not we get it out is another matter?"

"About the king… was that something your system told you?" Aaron asked.

Mark blinked. "No…No. I just sort of, of um, put it together. It's what I'd do if I wanted to fuck with somebody."

Aaron knew he was lying, but that didn't mean his suggestion was a bad idea.

"Come on then, let's check the river."

Mark had been dead right. Again. They found the key the moment they came to the river. It was wrapped around a massive boulder Aaron suspected King Bumi had personally chucked into the flowing water.

Aaron stared at it for close to a minute before he nodded to Mark.

"You're going to have to get that key to the surface somehow. My Airbending can't help here, and that rock is too heavy to move physically."

"You can't be serious?" Mark said. "I just started bending. There's no way I'll be able to lift a fucking boulder from the river floor with no training."

"Maybe not," Aaron conceded while he rubbed his chin, "but you can shatter it. Lifting a chunk of earth with the key still attached should be several times easier."

Mark mulled it over, still flustered. "Any hints on how to shatter a boulder?"

Aaron shrugged. "I'm an Airbender; what do you think?"

"Right…" Mark's frown deepened.

"But," Aaron added, "what you're talking about does remind me of one of my favourite Airbending moves, air blade. It took me nearly a month to get it down, but I was able to shatter chains the day I managed to do it. It's about funnelling your chi and movements into a powerful singular point and releasing it in a crescent." Aaron demonstrated with a quick spin and a sway of his hand. The river surface erupted, sending water drizzling down.

"Oh," Mark said. "It's that move you spam when you fight."

Aaron shot him a look, but the boy wasn't wrong. He'd stuck with the twin curved blades because they made his air blades so lethal.

"Anyways… you won't have to deal with resistance from the water. Just root yourself and try to split the rock."

All the tension slipped from Mark's body as he fell into a modified feather fist stance, rooting himself deep into the ground. He took deep, deep breaths before he struck out with the fastest chop Aaron had seen the boy use. The surface of the bubbled, and Aaron spied a crack running through half the length of the boulder.

Aaron caught himself grinning, pleasantly surprised, and Mark went still.

"Again!" Aaron roared, and Mark obeyed, shattering the boulder in one victorious roar. The river churned as the current pressed against the stone, but no key came loose, but that was no problem.

Aaron peeled off his shirt and ripped off his boots.

"What are you doing?" Mark asked.

"The key isn't just going to come loose," he said. "I'm going in, I need you to try to the rocks as soon as I dive."

Mark took a moment to mull it over but quickly gave a nod of consent. A moment later, Aaron was in the water, and Mark's face went purple as he tried to bend a chunk of what he could not fully see.

Aaron made his way to the bottom of the river, the current fighting him the entire way down. He found the key soldered onto a length of chain attached to a deposit of rocks and resisted the urge to click his tongue. The King was being absurdly petty, pulling a stunt like that, but Mark came through.

Slowly the stone started to budge, but it took an incredible effort to shift the stone aside and free the chain. Moments later, Aaron burst to the surface of the water just before he ran out of breath, key in hand, a grin plastered on his face.

Mark whooped at the sight, and King Bumi, who'd somehow snuck behind him, beamed.

"Finally, I was starving! Now we can all have some breakfast."

Mark jumped. "You were serious about the store room thing?"

"Of course," Bumi said in a solemn face. "I never joke about breakfast."

Aaron shook his head as he came to shore. "Does this mean we have time to rest before we attempt the second challenge?"

"I can't send you to the belly of the beast without something to give you energy. I'll have the chef whip up something spectacular."

Breakfast was silent, save for a few awkward barbs here and there. Sokka laughed at every bad joke the King told, and Aang listened to the stories of Bumi's younger years.

Soon, it was noon, and Bumi brought to a large pen with several small animals. The borders were moulded from earth and stretched farther than Aaron could see. He spied rabbits, deers, and possum hares, and he couldn't help but think the only thing the pen was missing was a predator.

"A predator, you say?" Bumi muttered thoughtfully. Aaron had been thinking out loud. "I don't know about that. If there is one, then I should be very worried. It's Mr Flopsy's playpen, after all. He might be in real trouble!" Bumi grabbed Mark by the shoulder, panicking.

"Oh no!" Sokka helpfully said, and Aaron rolled his eyes.

"You have to find him for me," Bumi said. "He might be in serious danger."

Aaron doubted that the pet was, but he played the King's game "What does Flopsy look like?"

"He's white, covered in fur, and has a helpful tag around his neck. You can't miss him?"

Mark, who'd been thoroughly shaken, steadied himself, holding his throbbing head. "He meant what kind of animal was he?"

"Quickly!" Bumi said, shoving them both towards the pen's entrance, "No time to be asking questions now. I need you to act fast. You need to save Flopsy!"

The second challenge proved not to be more of a prank than any real challenge. Mark saw through it the moment 'Flopsy' came bounding towards them. He was large, mouth spilling with razor-sharp teeth and limbs so thick they could snap bones. Yet, jingling around his neck was a tag that read 'Flopsy.'

All it took was for them to stand their ground, and the trial was over.

The absolute beast rolled over when Bumi hopped into the ring and treated him to belly scratches. Aaron couldn't keep the discomfort and confusion entirely to himself. It seemed unnatural for a man to have a pet that ferocious. But who was he to talk, the Airbenders had bisons, after all.

--

Happy birthday, Matthew. The bestest big brother in the world.