The Pokémon anime has been through many different eras, but one of the most enduringly popular has been the sixth-generation Pokémon XY era. The XY era not only saw Ash at his battling peak, but introduced his beloved companion Serena, who would go on to find a character arc of her own that helped strengthen their journey.

Serena is an unusual character in that she had a pre-existing relationship with Ash; the two had met long ago at a Professor Oak summer camp. This gave their relationship a little more depth, and explained why Serena seemed to have a crush on Ash right of the bat. Serena was just starting out on her journey when Ash arrived in Kalos, and hadn't yet found a goal for herself. Through traveling with Ash, Serena discovered a love of performing, and eventually began competing in showcases to become Kalos Queen. Ash and Serena were ive of each other's goals, which led to them growing closer throughout their journey.

A Battle by Any Other Name!

Pokémon XY, Episode #26

After baking some Poké Puffs, Serena sees them taken by a Slurpuff, whose owner derides the quality of the pastries. This triggers an instant rivalry between Serena and the Slurpuff’s owner, Miette, who also seems to have a little crush on Ash. Finding a poster for a Poké Puff baking contest, Miette and Serena agree to compete to see who is best.

Both Serena and Miette do well in the first round, but when they need to forage for berries, it becomes apparent that Team Rocket, also in the contest, are sabotaging the other competitors. Miette and Serena work together to send Team Rocket packing, but it’s unfortunately too late. Another winner is decided, and Miette and Serena agree to set their rivalry aside for next time--although Miette threatens to out Serena’s crush on Ash if she doesn’t do so first.

Party Dancecapades!

Pokémon XY, Episode #105

While traveling, Serena unexpectedly receives an invitation to a formal dance party, meant to celebrate the Pokémon Showcase circuit. Serena, too scared to ask Ash, asks Clemont to be her date, while Miette turns around and asks Ash, much to Serena’s chagrin. Jessie and James are also in attendance, and soon the party has its featured event: a tag battle, with Miette and James on one side, and Ash and Serena on the other. They battle hard, and Serena’s Eevee ends up evolving into Sylveon!

Evolving an Eevee into Sylveon is no small feat, and it goes to show what a skilled trainer Serena has become while traveling with Ash. They’re even able to win the tag battle, thanks to their excellent teamwork. It’s a high-class party that shows what an impact Ash and Serena have made on the Kalos region, and there’s more yet to come.

A Showcase Debut!

Pokémon XY, Episode #60

Serena has finally decided what her goal is: she aims to compete in Pokémon Showcases, win three Princess Keys, and at last become the Kalos Queen! It all starts here in Coumarine City, where Serena will be competing against Shauna, a disguised Jessie, and several others. Things get off to a good start, but Fennekin ends up tripping on a ribbon, getting Serena eliminated from the competition early. Serena is upset, but resolves to do better next time. She gives herself a haircut and a new look to symbolize her commitment.

This is a big episode for Serena, both in establishing a goal for herself and in dealing with loss. Many fans consider Serena’s change of look here to be an important moment for her character, signaling a moment of growth as a trainer and as a person.

A Frolicking Find in the Flowers

Pokémon XY, Episode #89

As the group heads to Anistar City, they discover a grove of flowers, where an Eevee is dancing and frolicking through the meadow. Serena takes a liking to Eevee, but Ash accidentally scares it off, prompting Serena to search for it once again. She ends up putting on a show to attract its attention, but as soon as Eevee shows its face again, it’s nabbed by Team Rocket. Ash and Serena are able to make Team Rocket blast off, and Serena convinces Eevee to her team, becoming her next Showcase Star!

Eevee is a major capture for Serena, albeit one that happens a little late in the story. This Eevee becomes a key member of her showcase team, and marks a big moment of change with her approach to Pokémon. Serena and Eevee have an instantly strong bond, which would go on to be shown in later episodes.

Battling with Elegance and a Big Smile!

Pokémon XY, Episode #64

While traveling to the next city, Serena performs some Showcase practice to help get ready for the next big event. However, Fennekin and Pancham get into a fight, and Serena becomes frustrated with both of them, going off alone to cool off. While out, Serena meets a girl named Ariana, who helps her to the close bond she shares with her Pokémon and encourages her to apologize to them. Ariana challenges Serena to a double battle, and after a rough start, Serena gains the upper hand, and Fennekin evolves into Braixen!

This episode proves that training Pokémon isn’t always easy. As living creatures with their own feelings, Pokémon can be tough to work with sometimes, but a good trainer always knows when to make it up to their Pokémon. While Serena never finished her battle with “Ariana,” actually Kalos Queen Aria, evolving Fennekin helps her regain confidence and prepare for the next competition.

Battling At Full Volume!

Pokémon XY, Episode #115

A Pikachu trainer and rocker named Jimmy hopes to challenge Ash to a battle, but there’s just one problem: Ash is sick, and if he hears about the challenge, he’ll never rest like he’s supposed to. To solve this problem, Serena decides to dress up as Ash and battle in his place using Pikachu. However, as they face off, Team Rocket busts in and tries to steal both Pikachu. Ash emerges just in time to help defeat Team Rocket, and Jimmy is shocked to learn he was up against Serena, not Ash.

This is a fun episode that sees Serena trying to impersonate Ash, showing what she really thinks of him. It teases the Ash/Serena relationship, as Serena helps to care for the sick Ash, and shows that Serena is a much more competent battler than most would expect.

Performing with Fiery Charm!

Pokémon XY, Episode #80

Heading to a Showcase in Dendemille, Serena soon finds out she’ll be up against Miette and a disguised Jessie once again. After an altercation with Jessie, Serena’s costume is ripped, and she begins to feel like all is lost, but soon gets herself together and repairs the outfit. The Showcase begins with a Poké Puff bake off, which Miette wins, but Serena makes it through to the next round. They then proceed to freestyle performances, which prove to be stiff competition. Serena emerges as the victor, however, earning her first Princess Key.

This is Serena’s first big victory, and it’s noteworthy for taking down both her major rival Miette and Jessie as well. It proves to Serena that she can actually do this, and gives her a big boost of confidence in her abilities. It also shows how Ash s Serena in her dreams, in much the same way she does for Ash.

Master Class Choices!

Pokémon XY, Episode #109

Arriving in Fleurrh City, Serena prepares for her next Showcase, where she’ll be competing for the third Princess Key that she needs. Up against a hometown favorite, Amelia, Serena has a difficult Showcase ahead of her. Competing with an Espeon and a Shiny Dragonair, Amelia is definitely a tough competitor. Serena follows up with Braixen, Pancham, and Sylveon, and manages to outscore Amelia, winning the contest and her third key. Serena is now set to enter the Master Class, and compete for the title of Kalos Queen!

Another major victory for Serena, this Showcase pushed her to the limits, but she still seems to be lacking something important. The episode sees Serena being a bit reflective after her win, and with the competition really heating up in the Master Class, Serena will need to figure out what she’s missing to win.

Till We Compete Again!

Pokémon XY, Episode #140

The final episode of XY sees Ash headed home to Kanto, while Serena decides to go to Hoenn to participate in the Pokémon Contests of that region. The group also says goodbye to Alain and Mairin, Ash’s competitor from the final round of the Kalos League, who set off on a quest of their own. Clemont and Bonnie come to see them off, but Ash is in for a real surprise when Serena gives him a quick kiss goodbye.

This episode is infamous for being the only one where there’s a real hint of romance for Ash, although the kiss takes place mostly off-screen. It goes to show just how far Ash and Serena have come on this journey together, and that they’ve grown exceptionally close. Whether Ash reciprocates Serena’s feelings is never made clear, but there can be no doubt that Serena’s feelings for Ash are very real.

Seeing the Forest for the Trees!

Pokémon XY, Episode #121

After losing rather badly to Wulfric and failing to utilize the Ash-Greninja transformation properly, Ash is quite upset, and spends some time alone out in the woods. Serena goes out there and makes an effort to cheer him up, but Ash is in no mood, and the situation quickly turns into a fight. Serena heads back, leaving Ash alone in the woods. As Ash considers apologizing for his behavior, a snowstorm hits, forcing him to hide in a cave and causing Serena no end of worry. Greninja ends up saving Ash, and he gets it together once more.

While mostly an Ash episode, this episode does highlight how important Ash and Serena have become to one another. He actually thanks her for helping him see where he went wrong, and shows that he values her quite a bit. It’s rather unlike most of his interactions with past companions, and signals that Ash and Serena definitely have a special relationship. For this reason, this episode is certainly one of the best episodes of Pokémon XY focusing on Serena.