This may be Misaimed Fandom. It was not presented as a good thing, and it was Ash only moments away from becoming an Axe CrazyPerson of Mass Destruction. Oblivion's Shadow wasn't at full power, and he managed to turn the tables soon after. It is a hollow moment.
The first time you see Ash whupping anyeveryone's ass right after the prologue.
Team Rocket, of all people, using a mecha to snatch Meowth out from under the nose of an omnicidal sorceress, then self-destructing the mecha to blast off as a getaway.
Charlie, after much torture and total mind raping, sits like a lump for most of the fight with Gal. What snaps him out of it? Seeing his wife, Charla, in danger. And he kicks ASS.
Followed by Team Auraforce finally finishing off Gal once and for all. Helped by Charlie severing Gal's Red Orb powers by ripping his arm off.
Everything Sam and Max do. Max fought Leviathan in an RPG style turn based battle (long story). Leviathan has infinite HP. And MAX WINS.
Everyone in the Dusty Ditch gets a chance at this. From fighting various monsters without breaking a sweat, to kill three, count them THREE, Frost Giants.
I am pretty sure Darkrai got one when he got around (with loopholes and the like) his contract when confronted by Oblivion's Shadow and stunned, shocked and humiliated him in the process
Ash charges through a mass of Nihlator battleships, all while under fire from their guns AND the legendary birds, and, with help from his friends, gets through it all and successfully purifies the most powerful Shadow Pokemon the Nihilators have.
How about Leo, of all people, threatening Nuken, revealing half a dozen weaknesses, one Nuken himself wasn't even aware of, and then explains he's figured out how to kill Nuken before the guy can blink. And then saying that even if none of those did work, the countermeasures in his shell would kill Nuken for him.
Earlier, Lily gets one herself by standing up to one of the most feared Pokemon in the world, by sticking up for Leo and epically calling him out. This coming from the Mon who was a miserable, abused slave under her mother.
All of Chapter 62.
Professor Oak managing to break Doctor Tarantulas, and snapping Raikou, Entei and Suicune out of their brainwashing. It was immediately cancelled by Tarantulas, but still.
Legion has been running a scheme for the past millions of years, which culminates in imprisoning Rayquaza in Wyvern Hill forever and thus trapping the Guardian of Light in Kanjohenn.
Then Darkrai successfully escapes with Cresselia and Ho-Oh.
The chapter long fight scene that is Chapter 63. Every second of it.
Starting off, we have Leo fighting Arackaiser using his new Rider powers, which are all based on comic book heroes, and uses one of his new techniques to replicate the Teenage Mutant Ninja Squirtles from his town's past.
Next, we have Pikachu fighting Suicune. It's amazing, mostly due to Pikachu turning into an unstoppable monster of lightning, creating a Rapidash with a mane of lightning, creating a dragon out of lightning, summoning up every former member of the Thunderblade line, meeting the ORIGINAL Thunderblade, and earning his name, Tenjin.
Captain Briney effortlessly destroys Entei, without using any psychic powers, his new hammer, magic and had three arms tied behind his back. Oh, and he's apparently fought Balrogs.
Dawn does the same thing as Pikachu and summons up the entirety of her clan made of ice. She then shows what a ninja can do by outsmarting Paul and his invincible armour. Then she reveals that she's been taught the Seventh Slash, just before impaling Paul on an icicle. Finally, she evolves into a Lopunny, at which moment Pikachu proposes to her.
Professor Oak of all people gets a few moments. First of all, he's apparently this world's version of Indiana Jones. Secondly, he lays a psychic beatdown on Tarantulas with two little words: Trick Room.
Hubie's past is finally revealed. Turns out he was the former leader of Team Quantum. They had a disagreement on how to secure a better future, and stripped him of his memories before throwing them to the other end of the universe. Ordinarily, these memories would be gone forever. However, almost nothing is out of reach of The Eleventh Doctor!
Oblivion's Shadow and Gardevoir finally fight. It's absolutely insane, as Shadow is fueling himself with Shadow Aura to speed up his strength and reflexes, while Gardevoir has fully embraced her vampire side, making her practically immortal, and thanks to drinking every last drop of blood in Shadow's lab, she's at full strength.
Made even better by, immediately after the fight, Shadow sees the world wide news broadcast and realizing that his top people, save for Bellum, are all dead or free. Darkrai then pops up, points out that the contract between them is now null and void, and that he planned everything, from one of his vampires from another dimension turning Gardevoir, to getting those same vampires to grab Cresselia and take her out of there.
And, after seeing this, Mewtwo tries to get him to turn himself in. It would have worked, too - sadly, the Ruler of Evil (?) doesn't particularly want to.
As of Chapter 65, we have The assault on Mars!
Team Aurabolt unleashes their full power, all directed at Lord Null.
Ash and Sasha Mega-Evolve, which actually manages to make them even more powerful. Plus, Tiny's bond with Ash gives him a boost as well.
Tenjin summons armour, a dragon and a new Thunder Fang all made out of pure lightning, while summoning the spirits of his ancestors to help him fight. Dawn does the same as well, and at this point they have a small army.
Then Leo powers up into his new Masked Rider form, while Lily activates her new fire powers, which she dubs "Inferno Lily".
Micheal summons EVERY DEAD SPIRIT OF MARS to fight all at once, Boa uses Growth to become a Serperior bigger than the Peeko XIII, and Nosferatina becomes a giant Noivern.
Briney being Briney, doesn't need a super powerful magic form. Doesn't stop him from joining in with the transforming, though. As in, the Peeko XIII is now a GIANT ROBOT named the "Dai-Peekoger Z!". Everyone refers to it as a "Giant Golden Pirate Robot".
After all of this, Lily opens up thousands of portals around the planet, allowing THOUSANDS of Pokemon through. Among them are almost EVERY Pokeranger, Judgement and Team Getem who are wearing the Plates of Arceus.
And then the Lunar Armada joins in, with Darkrai, Cresselia and Ho-Oh leading them. Within seconds, they utterly DESTROY the Nihalators on the surface, which distracts Null long enough for the heroes to rescue ALL of the hostages.
After all of this, Lord Null is simply floating there... and he's absolutely STUNNED. For once, he has absolutely no idea how to deal with the situation, the heroes have caught him completely off guard.
Lord Null: NOT POSSIBLE. NOT POSSIBLE. NOT POSSIBLE.