The Pokémon anime is renowned for how much liberty it takes with the rules established in the Pokémon games. It ultimately comes down to telling an entertaining story. However, sometimes, Pokémon, especially Ash Ketchum's Pokémon, do something in a battle that doesn't jive with the rules.
These aren't violations of written rules, considering the anime has played a little loose with the rules of battle at times. Also, there is a difference between a battle in the wild and a battle in sanctioned league play or at a gym. Finally, sometimes the rules that are broken are unspoken courtesies to other players or Pokémon.
10 Pikachu Refused to Battle When Ash First Got Him
In his very first battle, Ash only had one Pokémon to call on, Pikachu. Of course, Ash and Pikachu hadn't bonded yet. When confronting a Pidgey in the wild, Pikachu refused to battle for Ash and watched Ash foolishly try to capture the Pidgey himself.
Ash's efforts make the pair the target of several Spearow. After being pulled from a river by Misty, Ash takes her bike, wrecking it before standing up to the Spearow to protect Pikachu. This earns Ash Pikachu's respect and loyalty. It also launches one of the strongest friendships in Pokémon.
9 Greninja Undergoes Its Own Version Of Mega Evolution Without A Stone
A Mega Evolution is a powerful tactic Pokémon trainers can call upon in a battle. Traditionally, it's triggered with a stone. Ash's Graninja broke this unwritten rule almost immediately after evolving. The episode was "A Festival of Decisions" from the series Pokémon the Series: XY.
Shortly after evolving into Greninja, the Pokémon was inspired by Ash's encouragement to change into a new form that would later be referred to as Ash-Greninja. This phenomenon is very similar to Mega Evolution and is only possible due to the bond Ash shared with the Pokémon. So far, Ash is the only trainer to use it, something that gives him a surprise advantage in battles.
8 Haunter Disappears During Battle
During the episode "Haunter Versus Kadabra," Ash and his friends meet a truly spooky opponent in Sabrina. Ash is confident now that the Ghost Pokémon, Haunter has joined them. Unfortunately, after Sabrina brings out her Kadabra, Haunter disappears, nowhere to be found.
Haunter disappears during a second battle, prompting Pikachu to bravely battle Kadabra. During the battle, Haunter appears beside Sabrina, attempting to make her laugh. This ultimately gets her to break into laughter, dropping Kadabra's Poké Ball. Sabrina's father declares Ash the winner.
7 Pikachu Aimed For Rhydon's Horn
In the episode "Riddle Me This," Pikachu finds itself faced against a Rhydon. Rhydon's tough hide was immune to Pikachu's electrical attacks. Being a Ground/Rock Pokémon, he's immune to electrical attacks, presenting a problem for Pikachu.
Ash then gets a ridiculous idea and tells Pikachu to aim for Rhydon's horn. Somehow, it works since the horn acts as a lightning rod, bypassing the armor. Unfortunately, this leads to the Gym Leader Blaine's signature Pokémon Magmar. Magmar is too tough for Pikachu and Ash forfeits rather than see Pikachu fall into the lava around the battlefield.
6 Primeape Refused To Follow Commands
Ash has had his share of obedience problems with his Pokémon. The most memorable of these was Charizard, but Ash also had problems with his Primeape. The Primeape was overly violent, especially after first evolving and beating up Team Rocket.
In the P1 Grand Prix, Ash has to use Primeape. In the very first match against a Machop, Primeape refuses to listen to its trainer. Of course, the price for its disobedience is a trip out of the ring. When Ash expresses concern for Primeape, the Pokémon begins to listen to his trainer on his way to win the P1 Grand Prix.
5 Mr. Mime Battled For Ash, Despite Not Being His Pokémon
Ash's Mom had her own Pokémon, Mr. Mime, who quickly became a focus of speculation and fan theory. He was never far from Ash's Mom, even journeying with her to Alola to visit Ash. He even was often referred to by the affectionate nickname "Mimey."
In the Netflix series, Pokémon Journeys: The Series, Professor Oak, Mr. Mime, and Ash's Mom are present when Ash and his new friend Goh are offered roles as new research assistants at the Cerise Laboratory. She leaves Mr. Mime to watch over Ash. Ash later uses Mr. Mime in battles, despite that not being the reason his Mom left her favorite Pokémon with her son.
4 Charmeleon Disobeyed Ash When Ash Was Trying to Help A Paras Evolve
In the episode The Problem With Paras, Pokemon trainer Cassandra is trying to get her Paras to evolve, so she can use the mushrooms from its Parasect form to create medicine. Ash decides to help by letting it win a battle against one of his Pokémon. Unfortunately, Ash uses his Charmeleon.
Charmeleon has lost respect for Ash and refuses to go easy on Paras. When Ash tries to reign it in, Charmeleon blasts him in the face as well. Pikachu helps, but only a desperate attack by Paras manages to give it a win against the disobedient Charmeleon, allowing it to evolve into Parasect.
3 Pikachu Used the Sprinklers To Defeat Brock's Onix
Early in the Anime, Ash encountered Pewter City gym leader Brock. Ash challenges Brock to a battle after being on his journey with Pikachu for just two weeks. It ends badly for Ash, with Brock's Onix humiliating Pikachu.
For the rematch, Pikachu easily takes down Brock's Geodude, prompting Brock to once again bring out Onix. Pikachu's electrical attack doesn't hurt his opponent, only damaging the gym. It looks bleak until the sprinklers go off from the damage. This weakens Brock's Onix, giving Pikachu an advantage that Ash is at first eager to use before reconsidering at the urging of Brock's siblings. He determines that winning in such a way would be wrong.
2 Pikachu Dynamaxed Without a Dynamax Band
In Pokémon Journeys, Ash and Goh find a Dynamaxed Drednaw wreaking havoc and endangering a stadium of spectators. Ash and Goh try to lure it away but are ineffective with their Pokémon. Pikachu then steps on a crack that is leaking raw Dynamax energy.
Leon noticed that Ash wasn't wearing a Dynamax Band. He offers advice since Ash is inexperienced in Dynamax battles. Normally, a Dynamax band is needed to empower a Pokémon in this way. A Poké Ball is also usually involved, but Pikachu bypasses that step as well. The crack of Dynamax energy isn't quite explained completely, though.
1 Charizard Battled Low-Level Pokemon
Ash's Charizard was never very obedient or cooperative. However, it began to listen to Ash more over time. In the episode "The Double Trouble Header," Ash meets Casey, a new trainer with an affinity for Electric-type Pokémon. In their first battle, Ash sends out one of his most powerful Pokémon, Charizard.
Misty and Brock question why Ash would use such a powerful Pokémon against a new trainer. She obviously couldn't have many, if any powerful or advanced Pokémon in her collection. Charizard doesn't choose this moment to show discretion and embarrasses the new trainer, sending her off crying. It shows not only what kind of trainer Ash was becoming in his overconfidence but also what kind of Pokémon he had in Charizard.