Ash and Leon's Full Battle in the Masters Eight Tournament finals continues. While Ash is in the lead in terms of remaining Pokémon, with him having four compared to Leon's three, his team members are getting exhausted from the fighting they've already done. His Dragonite begins the newest matchup against Leon's Rillaboom by countering its Drum Beating with Hurricane, dealing super effective damage. Rillaboom responds to this by beating its drum even harder, making the roots block most of the move and pummel Dragonite down to the ground. Due to Drum Beating's effect, Dragonite also suffers a Speed drop as it stands back up. Ash follows up with the "Dragonite Meteor" strategy that defeated Dragapult, but Leon is prepared for it now and has Rillaboom swat all the meteors away with Drum Beating before producing another root to grab Dragonite à la Vine Whip and send it back to ground once more. Dragonite roars with determination and immediately charges back in with Dragon Claw, which Rillaboom meets with Acrobatics, nimbly moving around the flurry of Dragon Claws before dealing the finishing blow with an open-palm thrust, showing off how Leon can handle opponents even while at a type disadvantage.
The next Pokémon to rejoin the battle on Ash's side is Sirfetch'd. The two physically oriented Pokémon clash with Meteor Assault and High Horsepower, putting raw power against raw power. Ultimately, Sirfetch'd wins the clash of brute force and sends Rillaboom flying back. However, Rillaboom is still not out yet and stands back up while leaning on its drum. With Sirfetch'd momentarily immobilized due to using Meteor Assault, Rillaboom gets a free chance to attack and sends Sirfetch'd flying with High Horsepower before following it up with Drum Beating. Sirfetch'd glides towards Rillaboom by riding on its shield and dodges the roots as it prepares to use Fury Cutter, abandoning its shield when Rillaboom leaps towards it with Acrobatics. Grabbing the discarded shield, Rillaboom disrupts the Fury Cutter before it can make contact by throwing the shield right back at its owner and then slamming Sirfetch'd itself down to the ground. The Wild Duck Pokémon struggles to stand back up but ultimately fails to do so. In just two rounds, Leon has turned the tide and made himself the one with more Pokémon remaining in his usable arsenal.
Leon thanks Ash for having given him the chance to show off his full potential; however, he also feels sad at the thought that this exciting battle is going to end soon. Ash declares that the match isn't over yet and sends out Dracovish, who's still utilizing the glowing spikes it awakened earlier. A clash between Drum Beating and Ice Fang ensues, and while Dracovish is momentarily thrown back, it quickly pins the roots down by sticking its spikes into them and then biting down on them. The ice-covered roots shatter within seconds, much to Rillaboom's frustration. Dracovish continues its assault with Dragon Rush, carrying on the spirit of its fallen friend Sirfetch'd as Rillaboom meets the attack head-on with High Horsepower. The two powerful moves clash as Rillaboom attempts to push back, but its stamina finally runs out and it collapses, evening the odds once more. Leon responds to this knockout by sending out the Pokémon that started this battle, Cinderace, who wastes no time in dealing a big hit with High Jump Kick, its Libero Ability changing it into a Fighting type in the process. A collision between Water Gun and Pyro Ball follows, canceling out both moves. Dracovish next tries to land a Fishious Rend, but is countered and sent flying back by an Iron Head. With Dracovish visibly running low on energy, Ash is determined to make the next attack land and orders a Dragon Rush. Cinderace charges in with High Jump Kick and jumps over Dracovish's attack at the last second before landing its own attack from above, bringing an end to the Fossil Pokémon's time in the battle.
With Ash only having one Pokémon left to his name, Leon recalls Cinderace so he can finish the match with his ace, Charizard. As Ash's last Pokémon, Pikachu, reenters the battlefield, Leon takes a moment to reveal to Ash how Charizard was the first Pokémon he ever caught and battled with, making them inseparable, lifelong partners with a long history together. Ash assures that the same also stands true for him and Pikachu, which is why he intends Pikachu to be the one to defeat Charizard. Smirking at Ash's confidence, Leon declares that them being partners is the reason why he intends to finish this with Charizard, recalling his partner and Gigantamaxing it. Unfaltering, Ash calls for a Thunderbolt, which Charizard counters with Max Rockfall. While Pikachu succeeds in jumping over the move, the brief sandstorm created by the Max Move disrupts the Thunderbolt before it can go off. Despite this, the jump Pikachu made to avoid the attack has put him on an even level with Charizard's head, allowing him to land an Iron Tail on it. Gigantamax Charizard doesn't even flinch from this hit, however, and as Pikachu lands back on the ground, Charizard surrounds him in a vortex of Max Wyrmwind. Although Pikachu manages to endure the attack, Ash can't help but be impressed by the power of Gigantamax. Glancing at his Z-Power Ring, he knows there's only one thing he can do to match that power and tosses his hat to Pikachu. With Ash's friends, family, and Pokémon from Alola watching everything through television, Ash executes his and Pikachu's signature Z-Move, 10,000,000 Volt Thunderbolt. His excitement peaking, Leon meets Ash's full power with his own and orders Charizard to use G-Max Wildfire. The ultimate Z-Move and Charizard's G-Max Move clash in a display of power that shakes the entire Wyndon Stadium and creates a giant vortex of fire and electricity. Leon exclaims that he's always dreamed of pitting Gigantamax against a Z-Move, which Ash agrees with as well.
While the two devastating attacks continue their struggle for dominance, in Hammerlocke, Professor Magnolia is observing Eternatus at the Energy Plant beneath Hammerlocke Stadium, noticing that the Legendary Pokémon's Galar particles are reacting in a way she's never seen before. With a roar, the Gigantic Pokémon unleashes a Dynamax Cannon into the air and breaks out of the Stadium. As Professor Magnolia fears the possibility of another Darkest Day, in Wyndon, the clash between Ash and Leon's ultimate attacks ends in a devastating burst of energy. However, despite Charizard's Gigantamax state ending following its third attack, the dark clouds over Wyndon Stadium do not disappear like they usually do. In the audience, Sonia theorizes that the clash of Gigantamax and a Z-Move, combined with Ash's earlier use of Mega Evolution, is the reason behind this unusual situation. Things only continue to get all the more unexpected and unusual when Eternatus suddenly appears over the Stadium and lets out a loud roar.