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1. Who does Ash actually EARN his first Gym Badge from on his own? Other trainers advice at any point counts as not earning the badge on his own.
While they state he did earn his badge against Lt. Surge, Brock gave him advice on his Raichu's biggest weakness, that it evolved too soon. So he make the plan to use speedy moves that can only be learned in the Pikachu stage against it. This means Brock gave outside help and basically made the plan. Meanwhile Ash earned the Soul Badge completely on his own.
Koga
Lt. Surge
Falkner
Bugsy
2. What what was the first Legendary Pokemon Ash defeated, counting the movies?
Ash may have used Charizard against Roland's Articuno, but the only reason this is ranked so low is because he could have chosen to fight a different Pokemon but chooses challenge mode. He also wouldn't have won if Roland didn't tell the ref to wait a bit before making the call that Charizard fainted. Even so, beating a Legendary Pokemon in the anime is no small feat, especially in a 1v1, this is the only time in the anime, counting movies, where a single non legendary beats a legendary by itself. The only other legendaries to faint in the anime were Tobias's Darkrai and Latios, who both took down 3 of Ash's Pokemon before that happened, Goh's Suicune, who wasn't defeat by a Pokemon but by Pokemon Hunters weapons, and the lake trio, who were technically defeated by Jay in a 3 v 2 with the 2 being Jay's Salamence and Jay herself. This feat is even more impressive when you realize that in Journeys Goh teamed up with 2 other trainers, including Gary, against an Articuno and lost.
Articuno
Darkrai
Celebi
Latios
3. How many Legendary Pokemon has Ash defeated in battle, even noncannonically?
Ash has defeated Roland's Articuno, Brandon's Regice, Tobias's Darkrai and Latios, Gladion's Silvally, Tapu Koko, Eternatus and Mewtwo (during the Special Episode "Mastermind of Mirage")
6
7
8
9
4. Which Legendary Pokemon has Ash caught?
Assuming you count Ultra Beasts as Legendary, Ash caught Poipole which later evolved into Naganadel. The same can be said for Meltan. As for Eternatus, even though only Goh's Pokedex shows he caught it, the Dynamaxed Pokeball was thrown by both him and Ash at the same time, so Eternatus was caught by both of them.
Naganadel, Eternatus, Melmetal
Eternatus, Meltan, Poipole
Poipole, Melmetal, Eternatus
Meltan, Eternatus, Poipole
5. What was the first Legendary Pokemon that Ash met cannonically? Unless brought up by someone in the main series, Pokemon met in the movies don't count.
In the series, Ash only SAW Ho-oh, but never actually met one. However, in Pokemon Movie 2000, Ash met Zapdos first at Fire Island. This movie is considered cannon because it was specifically stated in the 213rd episode "Parent Trapped" that Ash has met Lugia in the Orange Islands, and ergo met Lugia too.
Moltres
Zapdos
Articuno
Ho-oh
6. During his battle with Gary in the Silver Conference, what was Ash's team when he won.
This is the first major battle where Ash didn't rely on Pikachu, and of all battles where we expected Pikachu, he had it sit in the stands. Also I'm sure all of use were too distracted on perhaps the most important battle of Ash's life to realize that Ash had seven Pokemon on him at the time since Pikachu wasn't chilling in Prof. Oak's lab. All and All, if going by species alone, this was Ash's best team at the time.
Charizard, Snorlax, Heracross, Bayleef, Muk, and Tauros
7. During the first movie, Ash battles a random trainer at the start, what was the first Pokemon he used?
I'm sure everyone was just as shocked as me (or Ash whenever Pikachu gets agitated) when a brand new Pokemon was just casually thrown out by a random trainer to begin the movie. Not only does this basically confirm they are making more Pokemon species for the years to come, it blew up the internet with theories about the Jhoto region.
Golem
Nidoking
Rhyhorn
Donphan
8. During Ash's battle for his Earth Badge, what Pokemon, given to them by Giovanni, do Team Rocket use at the start of the battle?
Considering later that Giovanni's Persian alone was able to battle Pikachu to a draw, it's suspected that all of these Pokemon must be on the same level if not greater, and Ash beat them all with one Pokemon against three at a time, which wasn't even Pikachu. It's also fascinating to see Pokemon that Giovanni never uses in the games.
Golem, Kingler, Arcanine
Nidoking, Nidoqueen, Rhydon
Onix, Kangaskhan, Persian
Machamp, Kingler, Rhydon
9. What made up move became a staple on Ash's team during his journey in Sinnoh?
While Ice Aqua Jet was a made up move, only Ash's Buizel has ever done it, and Buizel also has a Water Counter Shield. As soon as Sinnoh ended, Ice Aqua Jet was never seen again, but during his Battle with Leon, the Counter Shield made a comeback. It's honestly one of his best out-of-the-box ideas, and unlike most ideas, it wasn't a one-off. Even Fantina and Paul
Ice Water Gun
Ice Aqua Jet
Counter Shield
Spin Shield
10. Who does Ash's Infernape battle when it finally fully controls it's Blaze ability?
Even though it would be poetic for it to happen during a battle with Paul, or amazing to see against one of Tobias's legendaries, the moment it controls Blaze was still a defining moment in Ash and Paul's rival story. We all expected it to happen during Ash's final battle with Paul, so it gets points for being unexpected.
Barry
Volkner
Paul
Tobias
11. The only gym battle Ash LEGALLY swept.
Since Ash was accidentally cheating against Wattson it was illegal. Lt. Surge was a 1v1 so it can't necessarily be swept. And While Tate and Liza was a double battle, since the rule was defeating only one of the opposing Pokemon count as the win it was also technically a 1v1. Meanwhile Crasher Wake lost to Ash's team of Pikachu, who took down his Gyarados, Buizel, who defeated both Quagsire and Floatzel, and Turtwig. Not only that, from a strategic point of view this was Ash's most earned gym badge by far. Excellent switch-ins, keeping in the best type advantage pokemon as much as possible like Pikachu vs Gyarados and Turtwig vs Quagsire, where after Turtwig looked like it was about to lose Ash switches it in for Buizel after seeing Quagsire knew Ice Beam, an obvious set up for an Ice Aqua Jet. Best type match-ups from the Pokemon he had at the time even if Ash swapped Buizel for his Staravia, and most importantly a team wipe on Crasher Wakes side.
Wattson
Tate & Liza
Crasher Wake
Lt. Surge
12. Who strongest Trainer Ash has ever beaten from a team standpoint?
The variety of Pokemon on Cynthia's team was only one of the reasons people struggle against her in the games and why she is still known as the strongest Champion in them. Her team is her Platinum team, arguably her best team in the games. This is also an impressive victory for Ash because Sinnoh's Elite Four and Champion have almost always one-shotted every Pokemon they fought, the only survivors being Ash's Pikachu who took several of Flint's Inferape's attacks, Dawn's Buizel who withstood one attack from Lucian's Bronzong, and Dialga and Palkia matching Cynthia's Garchomp. The answer would have been Tobias if we knew what else he had on his team besides his Darkrai, who singlehandedly swept all his gym and league battles until he fought Ash, and Latios.
Paul
Cynthia
Gary
Tobias
13. In what region does Ash become Champion?
Ash first becomes Champion of Alola, but during the World Coronation, he defeated defeat Iris (Who became Champion of Unova at the time), Cynthia, and Steven Stone. Not only them, but Leon, effectively making him the World Champion. And long before any of this he defeated the Orange Crew League Champion Lance