Mimikyu has a rather dark personality, as Meowth was too horrified to even translate its words. Mimikyu also has an incredible, ferocious hatred for Pikachu, instantly siding with Team Rocket before it was even captured. It is shown to be psychopathic and violent, attacking Pikachu even against direct orders and mercilessly tries to pummel Pikachu even after he fainted. Should Mimikyu see Pikachu, something in its likeness, or hears the name, it will fly into a rage and be engulfed by blue flames.
Although Mimikyu is a powerful fighter, it usually doesn't help Jessie fight, unless Pikachu is one of its opponents. Despite its hatred for Pikachu, it did fight an Alolan Dugtrio and fought an Alolan Raticate, which was a Totem Pokémon. In truth, after Jessie helped it to fix its costume, Mimikyu's loyalty to Jessie has grown.
Mimikyu is also shown to have a habit of scaring Meowth. Meowth has (so far) had four near-death experiences after seeing the insides of Mimikyu. This also nearly happens to Jessie, who became horrified to see its true face when its ragged costume is torn.
Mimikyu also seems to have an extreme fondness for food, particularly malasadas. However, it also eats other tasty consumables, such as Berries and cream puffs. Furthermore, Mimikyu treats its ragged costume very importantly, and refuses to dress up in other costumes because it really hopes to be loved like Pikachu, in spite of its violent and hateful traits. It has the costume dried on a clothes line, as if it was actual clothing, though this scared Meowth again for a brief moment. If the costume is ever damaged, it wears a spare malasada bag as a substitute.
Mimikyu is also something of a prankster, as it sometimes scares Team Rocket while in dark or creepy places, and even took James' cream puff when it fell to the floor, much to his horror. When it is not in battle, Mimikyu prefers to roam around and do whatever it likes, being commonly seen moving outside Bewear's den.
Despite being the most brutal Pokémon who bears a hatred towards the Pikachu family (particularly its nemesis, Ash’s Pikachu), even Mimikyu has remaining standards, such as never mess with Bewear’s wrath, as seen when it was afraid of her anger towards an Ultra Beast Pheromosa, who manipulated and played Meowth’s heart into serving its purpose.
At the end of Team Rocket's time in Alola, Mimikyu saw its reflection in the water during its final battle with Pikachu. As Mimikyu was reminded of how horrifying its appearance was, it began to cry and forfeited the match with Pikachu, possibly feeling remorseful after being reminded of what it truly was. Afterwards, during a conversation with Meowth, Mimikyu finally learned that hatred doesn't accomplish anything and its better to embrace the future than staying stuck in the past. Soon after, Mimikyu's heart has changed for the better as it decided to let go of its hatred towards all Pikachu.
When Mimikyu debuted, it freaked Team Rocket out when it snickered sinisterly. When Jessie forced Meowth to battle Mimikyu, he impulsively uncovered part of its cloth and it killed him, causing Meowth to have his first near-death experience.
Later, Jessie, along with Wobbuffet, Meowth and James, who were hiding in Bewear's cave, saw it at the entrance. Jessie tried to throw two Poké Balls in order to catch it, but it used its "tail" to throw them away. However, when Jessie forcefully took away James' Luxury Ball and threw it at Mimikyu, she managed to catch it. It then fought alongside them to battle Ash and his Pikachu, as Team Rocket wanted to repay Bewear for the food it gave them by stealing the berries back that a Pikipek flock took. Mimikyu used Shadow Ball, which collided with Pikachu's Electro Ball. Pikachu went to use Iron Tail, but Mimikyu's Disguise made the damage nullified. To retaliate, Mimikyu used Play Rough on Pikachu. Just as it went to use Shadow Claw, Rowlet used Leafage and stopped Mimikyu, while Rowlet saved Pikachu by dragging him away to avoid Mimikyu's attack. Pikachu used Thunderbolt, which electrocuted it. Mimikyu attempted to use Shadow Ball, but was dragged away, along with the rest of Team Rocket, by Bewear.
Mimikyu, along with its Team Rocket comrades, went to the seaside after the Team Rocket Trio and Wobbuffet received a message from their HQ. Due to the hot weather, Mimikyu jumped into the water and left its costume for a relaxing swim, leaving the costume slowly soaking in the water. Meowth was shocked when he saw its costume, realizing its "body" was fake, and then died for a while after he witnessed Mimikyu in its real form. Later, after Meowth's soul returned to his body, he, along with Jessie and James were horrified when they saw the ruined "face" of Mimikyu's stuffed "head", showing that the costume's "face" was drawn with non-waterproof markers.
Jessie and Mimikyu joined the Great Alola Pancake Race. She ran with Mimikyu, determined to win the prize. However, Mimikyu noticed Pikachu and vengefully prepared to use Shadow Ball. Jessie realized something was wrong and ordered Mimikyu to stop the attack, but it disobeyed. The cart started going backwards and Jessie rushed to grab the cart, yelling out for the pancakes. When Pikachu, Nina's Raichu, Lana's Popplio, Mallow's Bounsweet and Mimikyu were crossing a bridge, carrying the pancakes, it was enraged at Pikachu's presence and used Shadow Ball. James and Jessie begged Mimikyu not to attack, as it was against the rules. Just then, Bounsweet fell down, causing the pancakes to fall on Mimikyu's plate. Mimikyu missed the attack and hit Popplio's bubble instead, causing the pancakes to fall on the ground too, making the three disqualified.
When Team Rocket cornered Lillie and Snowy, Mimikyu was ordered by Jessie to attack their opponents, but it simply walked away. Meowth and Wobbuffet figured out that it only fights when Pikachu is present. It wanted to fight against Pikachu when Ash, Mallow, their Pokémon and Rotom appeared, but Snowy froze it with its comrades, and Bewear took Team Rocket away yet again. When Jessie was being crushed by Bewear's hug, Mimikyu began to eat one of her malasadas by swallowing it whole under its costume through its body.
Mimikyu decided to save Jessie and its other comrades by using Wood Hammer and Play Rough on Totem Raticate, who managed to injure Team Rocket's other Pokémon. Mimikyu wins by the Totem's type disadvantage and injuries, allowing Team Rocket to get the Darkium Z.
After being blasted off by Turtonator's Inferno Overdrive, Jessie and Mimikyu got separated from the rest of the group. Unfortunately, its disguise was torn, forcing it to wear a paper bag. Jessie attempted to choose a new costume for it quite forcefully during her clothes-shopping, though this made it extremely fed up and chose to leave the shop. After Jessie gave Mimikyu encouragement and fixed its disguise, Mimikyu was deeply moved that it helped Jessie to defeat a group of wild Murkrow (despite scaring Meowth to death for the third time in the process) and even ate malasada with her. Team Rocket was later knocked out by Ash with Lycanroc's Continental Crush, owing to Mimikyu's disobedience and hatred to Pikachu. After Bewear saved them and took them back into the forest, the way that Jessie looked at Mimikyu could indicate that the bond between Pokemon and Trainer seemed to become a little stronger.
Sometime later, Mimikyu traveled to Ula'ula Island with Jessie, James, Mareanie, Wobbuffet, and Meowth. There, they obtained a Z-Ring from Nanu, Giovanni's former acquaintance, and a Mimikium Z from Acerola.  Mimikyu saw this as the perfect opportunity to finally defeat Pikachu, so it taught Team Rocket how to perform the Z-Move's pose in preparation of their battle.  Mimikyu later met up with Ash and Pikachu at the Thrifty Megamart so it can battle with them. Before Bewear was gonna bring them back to Melemele Island, Mimikyu stopped it and ordered it to wait. Mimikyu and Pikachu battled violently non-stop. Just as Pikachu was about to launch Electro Ball, Mimikyu performed the Z-Move, Let's Snuggle Forever. It may seem as though Mimikyu had won the battle and gave Team Rocket an easy win for them to finally capture Pikachu. Much to Team Rocket's horror, Pikachu somehow shielded itself with its newly learned move, Electroweb. Pikachu launched another Electroweb to trap Mimikyu, and Ash and Pikachu finished the battle when they performed the 10,000,000 Volt Thunderbolt Z-Move, which was something that Team Rocket couldn't comprehend if they used it before or not. With Mimikyu defeated and burned by the Z-Move, Bewear takes Mimikyu and the rest of Team Rocket back to Melemele Island.
During the Manalo Conference, Mimikyu was used in the Battle Royal preliminary rounds. However, it refused to obey Jessie's commands and attacked any Pikachu it saw in the conference. It battled against Pikarla's Pikachu and defeated it. But just when it was going to attack Ash's Pikachu, Jessie, fearing that Mimikyu would blow Team Rocket's cover, quickly recalled it back to its Pokéball, narrowly allowing Jessie to make it to the Top 16.
Soon after the Alola League, Team Rocket received a call from Giovanni and were ordered to return to Kanto due to their lack of achievements in Alola. Jessie and James, knowing that Mimikyu and Mareanie would be unhappy in Kanto, decide its best to leave them behind. However, unbeknownst to them, Mimikyu decides to take one last shot in defeating Ash's Pikachu for good. Mimikyu meets up with Ash and Pikachu at the beach and challenges them to one last battle. But during the battle, Mimikyu sees the reflection of its face in the water and is reminded of what a monster it truly is. Mimikyu falls into despair and loses its will to continue the fight. Mimikyu then sulks back to Bewear's den. It eventually meets up with Meowth and explains what happened. Upon hearing Mimikyu's story, Meowth tells it that hatred doesn't always accomplish anything and that its best to move forward towards the future than staying stuck in the past. With that, Mimikyu goes through a change of heart and finally decides to let go of its hatred towards Pikachu. As Mimikyu and Mareanie sleep, Team Rocket leave Alola and return to Kanto. The next day, Mimikyu is last seen playing with Mareanie and Stufful, now a more happy and cheerful Pokémon.
- Mimikyu is the first recurring wild Pokémon to be caught by Team Rocket. It is also their first one caught in a special Poké Ball.
- Jessie's Mimikyu serves as a complete opposite to its species' description: while most Mimikyu idolize, yet envy Pikachu, seeking to be loved just like it, this individual feels an intense and murderous hatred against Pikachu, only dressing up like one to serve as a psychopathic manifestation of its unrelenting hate.
- In "The Sun, the Scare, the Secret Lair!", Mimikyu is seen without its cloth, and it appears as a dark amorphous cloud with a pair of glowing yellow eyes.
- In "Getting to Know You!", it reveals that Mimikyu eats food simply by swallowing them with its body.
- ^ SM003: Loading the Dex!
- ^ SM004: First Catch in Alola, Ketchum-Style!
- ^ SM012: The Sun, the Scare, the Secret Lair!
- ^ SM013: Racing to a Big Event!
- ^ SM014: Getting to Know You!
- ^ SM025: A Team-on-Team Tussle!
- ^ SM038: Mimikyu Unmasked!
- ^ SM073: Why Not Give Me a Z-Ring Sometime?
- ^ SM075: Some Kind of Laziness!
- ^ SM076: A Battle Hand-Off!
- ^ SM090: Securing the Future!
- ^ SM129: Battle Royal 151
- ^ SM146
|Team Rocket's Pokémon|
|Jessie · James|