The Battle Tree, Ash vs Gary!

"Are ya sure that's the place?" Marnie questioned while Latias ferried her, Ash and Lillie through the Alolan sky.

"Definitely that wasn't here the last time I was here," Ash commented while gazing towards towards a tall that had been modified to have battling platforms stationed at various different levels. A battle could be seen taking place at the top as Hyper Beam and Dark Pulse attacks flew through the air around the battlefield. "That must be the Battle Tree that Gary was talking about."

Latias took them in for a closer look allowing them to see a Hydriegon locked in a heated battle with a Wigglytuff!

"Tuff!" Wigglytuff cried out while delivering a powerful uppercut to one of Hydreigon's multiple jaws.

"Hydre!" Hydreigon roared out before firing a Hyper Beam in response upon his trainer's command.

"Hey look, it's Grimsley!" Ash excitedly exclaimed upon spotting the current Dark type Master.

"Pi Pikachu!"

"I guess he's come to challenge Leaf and Gary." Marnie muttered. Now would be the perfect chance to arrange a time for the pair to battle it out but she still had to defeat Karen and Sidney to ensure that she could take him, she still felt as if she had a ways to go before she was Grimsley's level.

"And that is Leaf's Wigglytuff, I haven't seen it in action but I've sure heard about it. It's a very powerful Pokemon from what I understand, very few have beaten it." Lillie softly spoke.

"Tuff!"

"Hydre!" A loud thud was heard as Hydreigon's body slammed against the battlefield, swirls formed within all six of it's eyes as it groaned in defeat.

"Whoa!" Ash gasped out. He knew first hand how powerful Grimsley's Hydreigon was, it wasn't a Pokemon to be taken lightly and only a very powerful Pokemon would be capable of taking him down. 'Just who is this girl?'

Grimsley happened to glance up while shaking hands with Leaf, the Dark type Master flashed them a smirk of acknowledgement and offered them a light wave before turning to take his leave. Leaf looked up before forming a smirk of her own as she called out. "Oh Gare Bear, your best friend is here!"

"I noticed." Gary smirked while stepping out onto the battlefield. "Hello there Ashy boy, you ready for our scheduled Championship now? Man you're cutting it close, it feels like I've been waiting weeks for you to come by!" Gary playfully teased.

"It does feel like we've been flying for awhile." Lillie sweated.

"Well I'm here now Gary, Pikachu and I are ready to face you with everything we've got!" Ash eagerly shouted out.

"Pika pika!" Pikachu clenched his fists, his eagerness matched his trainer's.

Gary let out a laugh while giving his Rotom Phone a quick tap, summoning a Rotom Drone to their location. "Well we'll see about that won't we, after all from what I hear you had to beat a bunch of chumps to earn your championship title in the first place. If I was there, things would be different!"

Leaf winced at Gary's words but she made no attempt at arguing with him. Ash on the other hand had shot bright red, his clenches tightly clenched as he angrily retaliated Gary's words with some of his one. "My friends aren't chumps, Gladion and Guzma are some of the strongest trainers I know! How about we settle this right here?! If I win then you have to admit that you were won and if you win, I'll relinquish the Champion title to you!" Gary had been getting a rise out of him so much lately that he couldn't help but blurt it out.

"Ash..." Marnie facepalmed.

"Ash, you can't do that!" Lillie gasped out.

Gary rolled his eyes while flashing a playful. Ash reacted precisely the way he thought he would. "Alright Ashy boy, let's begin!"

"Bzzzt! Greetings Challengers Ash Ketchum and Gary Oak! This battle will consist of a four on four matchup and both trainers are permitted to switch their Pokemon out at any time. Additionally you may only use one of the following; z-move or Mega Evolution. Challengers are you ready to begin?"

"Ready!" Gary smirked.

"Ready!" Ash shouted out.

"Pika!"

"Then let the battle begin!"

"Incineroar I choose you!"

"Buzzwole, I'm counting on you!" Gary threw the Beast Ball forward causing Buzzwole to burst out onto the battlefield.

"Bzzzz!" The muscular bug Pokemon began flexing it's massive muscles.

"Roar!" Incineroar snarled as he stared the Ultra Beast down.

"Focus Punch!" Gary smirked.

"Bzzz!" Buzzwole's fist glowed a bright blue color as he lashed out, striking Incineroar's stomach!

"R-Roar..." Incineroar grunted out.

"Stay strong Incineroar, we've got this. Use Flamethrower!"

"Roar!" Incineroar thrusted outwards as a massive stream of fire erupted from his belt, the flames shot across the field before engulfing Buzzwole causing the Ultra Beast to screech out in pain.

Gary remained calm however as he thrusted his palm outward. "Stomping Tantrum!"

"Bzzzz!" Buzzwole slammed his foot against the ground causing a large chunk of the battlefield to splinter up, Buzzwole swiftly grabbed hold of it before hurling it through the air. The chunk of ground flew through the air before crushing Incineroar, knocking the luchador tiger onto his back.

"I-Incineroar..." Incineroar grunted out as he slowly rose back to his feet.

"Come on Incineroar you can do it, I got faith in you! Use Flare Blitz!" Ash shouted out.

"Pikachu!"

"Roar!" Red hot flames engulfed Incineroar's body and spiraled around him as he raced across the field. "Incineroar...!" Incineroar leaped up into the air before body slamming Buzzwole against the ground.

"Bzzzz!" Buzzwole grunted out, his legs and arms flailed about for a moment before going limp. Swirls were visible within the Ultra Beast's eyes as Incineroar climbed off of him.

"Bzzzt! Buzzwole is unable to continue battling, Incineroar wins!"

"Alright Incineroar!"

"Pika pi!"

"Thank goodness..." Lillie breathed out a sigh of relief.

A smirk briefly appeared on Gary's face before fading away as he recalled Buzzwole. "Great work Buzzwole, rest up for now."

"Bzzz..."

"Arcanine, I'm counting on you!" Gary shouted while hurling a standard Pokeball forward.

"Arooo!" Arcanine howled as he burst from his ball.

"Extreme Speed!"

"Arooo!" An orange-yellow blur was visible as Arcanine blasted across the field before knocking Incineroar down with extreme speed and force!

"Roar!" Incineroar stumbled onto his back once more but stayed there this time, his limbs went limp as swirls formed within his eyes. "Roar..."

"Bzzt! Incineroar is unable to continue battling, Arcanine wins the round!"

"Arooo!" Arcanine victoriously howled out.

"Incineroar return, don't worry you were great out there today. Take a good long rest." Ash smiled at the ball before placing it back onto his belt. "Alright let's fight speed with speed, Latias I choose you!"

"On it, Chosen One!" Latias screeched as she burst out.

"I told you to stop calling me that..." Ash sweated.

"Sorry, master!" Latias blushed while Ash inwardly groaned. Why was it so difficult to get Latias to use his actual name?

"Dragon Pulse!"

A multicolored beam of dragon shaped energy fired from Latias' mouth and struck Arcanine's paws causing the canine to yelp out.

"Heh," Gary smirked once more. "Play Rough!"

"Arooo!" Arcanine leaped across the field and tackled his opponent, a cloud of dust surrounded the two as Arcanine snarled out. Scratches and slashing could be heard for a brief while before eventually calming as Arcanine leaped away.

"Tailwind then follow up with Hyper Beam!" Ash shouted out.

"Lati!" A fierce and powerful wind whipped up behind Latias as she fired up an orange-yellow energy blast, the energy beam quickly fired across the field and strucked Arcanine causing him to yelp out once more.

"Dig!" Gary shouted out.

"Arooo!" Arcanine burrowed beneath the ground, disappearing from sight.

"Use your telepathy to locate him!" Ash swiftly called out.

Gary smirked while looking impressed. "Crunch!"

"Arooo!" Arcanine burst out from behind Latias and prepared to chomp down on her back but the Psychic type swiftly evaded his attack causing him to faceplant against the dirt. "Arooofff!"

"Psychic!" Ash shouted out.

Latias' eyes shot a bright blue color while a similar color surrounded Arcanine's body as he was lifted up into the air before Latias swiftly slammed him against the ground. Arcanine yelped before snarling as he leaped back to his feet.

"Play Rough!"

"Arooo!" Arcanine leaped across the field and pounced on Latias, a massive dust cloud formed around them as Arcanine rapidly slashed at her.

"L-Latiii!"

"Use Dragon Pulse!" Ash shouted out.

"L-Latiii!" A soft explosion could be heard within the dust cloud shortly before Arcanine's body was sent hurling through the air.

"Arooo!" Arcanine howled out before collapsing against the battlefield, his body went limp as swirls formed within his eyes.

"Bzzzt! Arcanine is now unable to continue! Challenger Gary Oak please send out your next Pokemon!"

Gary smirked once more as he recalled Arcanine to his ball before swiftly grabbing at another. "Electivire, I'm counting on you for this one!"

"Electivire!" The fully evolved Electric type excitedly exclaimed upon release, a soft thud could be heard as he landed against the ground.

"Wild Charge!"

"Electi...VIRE!" Yellow electricity sparked around before completely engulfing his body in a fierce some electrical glow, Electivire shot across the field in a flash before launching himself at Latias. An electrical shock soon flowed through Latias' body as he pinned her against the ground. "Electivire!"

"L-Latiiii!" Latias screeched out in pain before quickly collapsing from exhaustion as swirls formed within her eyes. "Latiii..."

"Bzzt. Latias is unable to continue battling!"

"Latias!" Marnie gasped out.

"That Electivire sure is strong." Lillie commented.

"Latias return," Ash gritted his teeth as he returned Latias to her ball. It made sense that Electivire would be there, he was one of Gary's main Pokemon and among the strongest. "Alright Decidueye, I choose you!"

"Hooot!" Decidueye cried as he burst from his ball.

"Spirit Shackle!"

"Hooot!" Decidueye pulled an arrow quill from his wing and quickly took aim before firing it towards Electivire's shadow, the arrow flew across the air before piercing the exact spot Decidueye aimed at as ghastly blue flames rose around Electivire's body.

"E-Electi..."

"Thunderbolt!"

"E-Electivire!" Electivire's body sparkled and cracked with electricity before a powerful electrical bolt fired from his body, the bolt flew across the air before giving Decidueye quite the electrical shock upon impact.

"H-Hooot!" Decidueye screeched out.

"Leaf Blade!"

"Hooot!" Decidueye's wing shined bright green as he swiftly shot across the field before slashing Electivire across the face.

"Electivire!" Electivire grunted out.

Gary smirked while pulling up the sleeve to his jacket, revealing a Z-Power Ring that was stylized after the purple shirt he used to wear. "Alright Electivire, let's show them our true strength!" He shouted, activating a bright yellow z-crystal before moving in synch with Electivire as they posed. "Gigavolt Havoc!"

"Electi!" A massive beam of electricity formed in between Electivire's hands as it charged up. "VIRE!" Electivire thrusted out his palms, forcing the powerful electrical blast to zip through the air as it made it's way towards Decidueye.

"H-Hooot!" Decidueye's eyes widened as he screeched out while the electricity surged through his bones. His eyes began to droop while his body swayed back and forth before eventually collapsing against the dirt as swirls formed within his eyes. "Hoot..."

"Bzzzt. Decidueye is unable to continue battling, Challenger Ash please send out your final Pokemon!"

"Decidueye return!" Ash whipped out Decidueye's ball, swiftly returning him before placing the ball back upon his belt. "You were great out there and deserve a long rest, alright Pikachu I choose you!"

"PIKA!" Pikachu's cheeks sparked as he sprang out onto the battlefield.

"Electi!" Electivire smirked as the pair locked eyes with each other.

"Iron Tail!"

"Chuuu!" Pikachu's tail glowed bright silver as he swung around before crashing his tail against Electivire's forehead.

"Darkest Lariat!" Gary shouted out.

"Electi!" Electivire held his arms out as he began rapidly spinning in place as dark purple energy surrounded his hands before flowing around him as the Electric type shot across the field. "Vire!" Electivire cried as he began rapidly smacking his palms against Pikachu's body!

"Chaaaa!" Pikachu cried as Electivire knocked him back.

"Hang in there Pikachu, we've got this!" Ash grabbed hold of his hat and tossed it into the air, Pikachu leaped up and caught it with his head before landing back onto the battlefield. The two began moving in perfect synch with each other as Ash activated his own z-crystal. "10,000,000 Volt Thunderbolt!"

"PIKA!"

Gary couldn't help but grin at the sight as storm clouds formed above Pikachu's head, Pikachu leaped up and began absorbing the electricity that gathered within the clouds. Colorful electrical sparks flowed from Pikachu's cheeks as he looked eyes with Electivire. "Pika...chuuuu!" He cried out as multiple colorful electrical bolts released from his body and shot across the field before making contact with Electivire.

"E-Electi-Vire!" The Electric type screeched out as the electricity surged through his veins. The Pokemon dropped down to a knee as he tried resisting the fatigue, he slowly rose back to his feet before promptly dropping to his side as swirls formed within his eyes. "Electivire..."

"Bzzzt! Electivire is unable to continue battling, Pikachu wins this round! Challenger Gary Oak please send out your final Pokemon!"

Gary returned Electivire to his Pokeball however rather than appear frustrated or upset with Ash, he appeared to be proud of him. Gary flashed Ash a sincere smile as he reached for his final Pokeball. "Umbreon I'm counting on you!"

"Umbre!" Gary's trusty Umbreon cried out as it appeared on the battlefield.

"Shadow Ball!"

"Umbre!" The ghastly energy ball formed within Umbreon's mouth and shot across the field before exploding at Pikachu's feet, knocking the Electric type back.

"Pi..."

"Thunderbolt!" Ash shouted out.

"Pikaaachuuuu!" Pikachu's cheeks sparked shortly before a powerful blast of electricity released from his body, the electrical blast flowed through the air before striking Umbreon's body causing the Dark type to cry out as electricity surged through his veins.

"U-Umbre!"

"Psychic!" Gary shouted out.

"Umbre!" Umbreon's eyes shot bright blue while a similar glow surrounded Pikachu's body as Umbreon telepathically lifted him into the air.

"Break free with Volt Tackle!" Ash shouted out.

"Pika!" Pikachu began rapidly racing in place midair as golden electricity began flowing around his body. Umbreon gritted his teeth as holding Pikachu up steadily became more difficult until he outright lost control as Pikachu blasted free of his telekinetic grasp. "Pika pika pika... PIKA!" Pikachu cried out as he slammed against Umbreon, knocking the Dark type across the battlefield. Umbreon shook himself off as he hopped back to his feet.

"Dark Pulse!" Gary shouted out.

"Umbre!" A pulse of dark static energy fired from Umbreon's mouth and blasted Pikachu, knocking the electric mouse back a few feet.

"Iron Tail!" Gary swiftly ordered out.

"You use Iron Tail as well!"

"Umbre!"

"Pika!" Umbreon and Pikachu's tails shined silver as they swung around and clashed them against each other, Umbreon and Pikachu flashed each other a challenging smirk as they pushed against each other with neither wanting to be the first to give up.

"Hyper Beam!" Gary shouted while taking advantage of the situation.

"Umbre..." The orange-yellow energy beam began charging within Umbreon's mouth. "ON!" Umbreon cried out as he blasted Pikachu, causing the mouse to fly back before swiftly being met by Umbreon's tail as Umbreon slammed it against his side!

"Chaaa!"

"Hang in there Pikachu, we've still got a chance at this!" Ash eagerly shouted while clenching his fists. "Use Surf then follow up with Thunderbolt!"

"PIKA!" Pikachu raised his paws into the air as a massive wave of water formed beneath of him.

"Heh," Gary smirked. "He actually taught Pikachu how to Surf..."

"Pikaaachuuu!" Pikachu fired an electrical bolt into the wave causing the water to become electrified as the wave rode towards Umbreon. Umbreon sweated and attempted to run away only for it to be in vain as the electrified wave came crashing down on top of him. Umbreon screeched out as electricity surged through him once more, hitting twice as hard due to his wet fur. Umbreon's eyes slowly rolled upwards as he fell to his side, swirls formed within his eyes as he uttered out a groan of defeat.

"Bzzzt! Umbreon is unable to continue battling, congratulations Ash Ketchum you're now 19,052 in rank and placed in Diamond Class! All your battles will be six on six from now on, assuming that your opponent is an equal or greater rank to yours. And you have four and a half months to reach the top 100 in order to qualify for the Master Cup Tournament! Going after somebody with a massive ranking would be ideal." The Rotom Drone advised before flying off.

"Alright Ash, you're in Diamond Class!" Marnie cheered, the Dark specialist threw her arms around Ash before planting a kiss on his cheek.

"Go Ash!" Lillie cheered.

Ash spaced off for a bit before gleefully laughing out. He was super close to being the number one trainer in the world, if he managed to beat somebody like Palmer and take their ranking then he'd be set! But he still had some training to do, beating Palmer wouldn't mean that he'd be capable of standing toe to toe with Lance, Cynthia and Steven nor possibly Iris and Paul considering they Alder and Diantha in order to earn their respective rankings. Not to mention the fact that Galar was working to replace the fallen Mustard. Going after the remaining Elite Four members scattered across the world while finishing his Sinnoh Frontier Brain quest was sure to be enough to ensure he was prepared though. But which Elite Four member? Though Ash would soon have his decision made for him as his Rotom Phone buzzed, alerting him to a World Championship challenger.

Ash pulled out his Rotom Phone and gasped out, recognizing the challenger as one of Galar's Gym Leaders. He didn't recall the name as it wasn't one of the ones that Zach faced off against but he vaguely recalled the Leader being a Dragon specialist.

Clapping could be heard causing Ash to look up from his phone, Gary could be seen standing in the same position as before while offering Ash a genuine smile and look of respect. "Congratulations Ash, you passed the test!"

"Y-You were playing me this whole time?!" Ash gasped out with a startled expression.

"Pika?!"

"Heh, yep!" Gary smirked while lightly shaking his head. "I thought if I riled you up that you'd go all out and hit me with all you got and I must say that I'm impressed, you've definitely grown since the Sinnoh days. You've become a powerful trainer and are definitely worthy of the Alola Champion title." Gary bowed. "It's an honor being your rival and best friend, I just wish that we could have really given it our all." Gary showed a brief look of regret.

"I know what you mean, I'm sure that Charizard's itching for a rematch with him!" Ash grinned. "Why don't we have one more battle with just the two of them?"

"Sounds like a plan to me!" Gary smirked while eagerly grabbing at a ball. "Blastoise, let's do this!"

"Charizard I choose you!"

"TOISE!" Blastoise slammed his feet against the ground and performed a combat stance while staring Charizard down.

"CHAR!" Charizard shot a powerful stream of fire into the air upon release.

"Alright Blastoise, let's show Ash our strong our bond's become with Mega Evolution!" Gary shouted while tapping a Mega Ring causing a bright pink glow to envelop Blastoise's body as he began transforming into Mega Blastoise!

"Charizard, let's-Oh wait..." Ash sweated upon realizing that he still didn't have a Mega Evolution stone for Charizard.

"Char..." Charizard sweated.

"Hm? What's the problem?" Leaf finally questioned. She'd been keeping quiet the whole time to avoid the fact that Gary had been playing with Ash, he'd warned her in advance so she wouldn't get mad at him.

"I er... don't have a Mega Stone for Charizard." Ash admitted.

"What?" Gary gasped out before quickly crossing his arms as he shook his head. "Well that won't do, I want to face Charizard while he's at his fullest potential!" Gary held up a finger as he walked away from the battlefield, disappearing back into the Battle Tree before reemerging with a bright yellow Mega Evolution stone that had a small flame at it's center.

"Here," Gary tossed it towards Ash while offering him a light smirk. "That is Charizardite Y, consider it a reward for beating me. I found it awhile ago and never found the time to raise a Charizard of my own so I think it's better off with you, besides Charizardite Y suits you!"

"Thanks Gary, I appreciate it!" Ash beamed before turning towards Charizard. "Alright Charizard, you ready to take on Mega Evolution?!"

"Char!" Charizard answered by shooting a fire stream into the air.

"Don't you have Charizardite X back there?" Leaf questioned. "Why didn't you go ahead and give it to Ash? It's not like either of us have a use for it."

"Nah, I've seen his Lumiose Conference performance. He's not earned that one yet." Gary stated with a light smirk.

"Charizard let's show everyone our powerful our bond truly is with Mega Evolution!"

"Char!" Fire shot into the air as a bright pink light engulfed Charizard's body before it faded away to reveal the form of Mega Charizard Y!

"Char!"

"Toise!" Mega Charizard Y and Mega Blastoise stared each other down. Leaf, Marnie and Lillie silently watched as the old rivals and best friends duked it out while sunlight harshly poured down upon the battlefield.

"Dragon Pulse!" Ash shouted out.

"Char!" The multicolored dragon shaped energy beam flew from Charizard's mouth and exploded upon making contact with Blastoise's body.

"Toise." Blastoise grunted out while sliding back a few feet.

"Water Pulse!"

"Toise!" Blastoise took aim with his multiple cannons before firing out multiple different pulses of water, each of them far larger than they'd normally be courtesy of Mega Blastoise's unique ability known as Mega Launcher.

"Flamethrower!"

"Char!" Charizard fired off a powerful stream of fire, his experience combined with the effects of the sun's harsh rays allowed his fire to combat the larger of Blastoise's water pulses while the other two whisked by before splashing against him. Charizard grunted out before giving his target a light glare as he intensified the flame's power causing it to overwhelm and evaporate Blastoise's water pulse!

"Whoa!" Marnie gasped in disbelief. She knew Charizard was strong but she wasn't expecting him to do that!

"Dragon Pulse!" Gary shouted out.

"Toise!" The multicolored dragon shaped energy beam erupted from Blastoise's mouth and struck Charizard, clipping his way as the flying lizard attempted to dodge.

"Char!" Charizard grunted out.

"Seismic Toss!" Ash shouted out.

"Char!" Charizard swiftly flew across the field and grabbed hold of Blastoise, digging his claws into the turtle Pokemon's body as he hoisted him from the ground before spiraling through the air.

"Toise toise..." Blastoise's eyes rolled about, his face turned green as motion sickness set in before Charizard ultimately dropped him causing Blastoise to crash towards the ground below.

"Withdraw, break your fall!"

"Toise!" Blastoise swiftly withdrew into his shell causing the crash to take noticeably less damage than it normally would have. Gary then flashed Ash a playful smirk while thrusting out his palm.

"Water Pulse!"

"Toise!" Blastoise fired out another set of water pulses towards his opponent, Ash wasn't as prepared this time so Charizard took a bit of a knock. The lizard grunted out as Blastoise knocked him from the air before swiftly leaping back to his feet, smoke flew from his nostrils as he uttered a snort of frustration.

"Stay strong Charizard, we've got something that Gary hasn't seen yet! Use Solar Beam!"

"Char!" Bright solar energy fired from Charizard's jaw and rapidly shot across the field before making direct contact with Blastoise's stomach!

"Toise!" Blastoise's eyes widened as the air was knocked right out of him, the giant turtle collapsed onto his backside as the pink light enveloped his body for a final time before fading away to reveal his defeated form.

Gary silently shook his head while offering Ash a proud smirk as he recalled Blastoise to his Pokeball.

"Alright Charizard, way to go!"

"Pika pi!"

"Char!" Charizard shot a celebratory stream of fire into the air before returning to his Pokeball.

"Congratulations Ash!" Lillie beamed.

"You were great out there!" Marnie cheered.

"I swear it's inconsistence on which of your Pokemon's the strongest, is it Pikachu or Charizard? The answer seems to fluctuate by the day." Gary remarked with a laugh. "Congratulations on your victory but just remember to not get cocky, beating me doesn't mean you're at Cynthia's level yet!" Gary playfully teased Ash.

"Oh give it a rest Gary, let Ash celebrate his victory!" Leaf exclaimed while wrapping her arm around her boyfriend's. "You could use a bit of relaxation yourself!"

"Heh, I suppose so." Gary laughed.

Leaf gave him a smirk before making eye contact with Ash. "Hey Ash, it's good to see you again after all these years!"

"Again? What do you mean? Am I supposed to know you?" Ash questioned with a light tilt of his head. Leaf uttered out a light gasp before placing her hands on her hips while maintaining quite the offended expression.

"You seriously don't remember me?! Me, you and Gary used to play with each other all the time as kids!"

"What?!" Ash gasped while looking towards Gary who gave him a light nod, showing that Leaf was telling the truth. "No way..."

So some stuff happened. Ash obtained Charizardite Y from Gary after beating him, matching the Sun/Moon method. While also entering into the Diamond Class section of the Championship! I also may have dropped a hint about something.

Raihan is Ash's next opponent, I figured it best to get him out of the way now so Zach and him don't fight him back to back or close enough. But many more are to come, there's still the remaining Elite Four members and Frontier Brains before Ash'll face off against the Champions of the world! Let me know if there's anything you'd like to see in the future :)