With each new generation of the Pokemon franchise, there is a new region to explore in both games and anime. In Generation 4, that was Sinnoh. The Sinnoh region was explored in PokemonDiamond and Pearl, Battle Dimension, Galactic Battles, and Sinnoh League Victors of the anime series.
While the series overall is long and filled with many adventures of Ash and the gang, the Sinnoh series packs in a lot of emotional payoffs and satisfactory moments that make it memorable. Ash, Dawn, and Brock get up to interesting things, and the lot below are the best of them.
10 Dawn Meets Pikachu
When we meet the female protagonist of Sinnoh for the first time, it is her tenth birthday, and that means she gets to choose her starter. After choosing Piplup, she sets off on her journey to catch cute Pokemon for her contest pursuits.
The first Pokemon she meets is Ash's Pikachu. While she attempts, and consequently fails, to capture Pikachu, she treats Pikachu's wounds and even saves him from Team Rocket's clutches. This is where the friendship between Ash and Dawn begins.
9 Every Professor Oak Appearance
Professor Oak is a beloved character. Appearing in the very first Pokemon episode, he became a regular character in the first season, and then recurring every so often. He shows up a few times in the Sinnoh series, either via call or in person.
Known to Dawn as a Pokemon poet, she often times urges the Professor to recite his poetry, and much to the dismay of Ash and Brock, Dawn often gets her wish. Although he is mostly there for comedic relief, it is always nice to see Professor Oak show up long after his home season and still be as iconic as he was originally.
8 Diamond Dandruff
A nickname earned due to some accident in her childhood, Dawn despises the moniker of "DeeDee," that is, Diamond Dandruff. Though it is funny to everyone around her, it brought home some trauma for the young coordinator with regard to the Pokemon Plusle and Minun.
She is especially put to test when she has to face off against Ursula and her Plusle and Minun. Ursula's cruelty gains a new form as she learns about Dawn's past traumas and tries to humiliate Dawn in their final face off in the Daybreak Town contest. Seemingly, Dawn is shaken for a minute, but with the encouragement and love from her Pokemon, she pulls off a satisfactory win, fair and square. She also puts the "Deedee" nickname and its baggage behind her.
7 Meeting Nando, the Minstrel
Meeting the Pokemon minstrel who "sings to the moon," Nando, was one of the moments that served a teaching purpose to Ash and Dawn. Still in the early stages of their friendship, they had the tendency to bicker loudly and often, and Brock often had to step in to separate them.
Their fighting reaches a whole new level when Nando tells them about his personal crossroads. He is undecided on whether he wants to pursue contests or league battles, and Ash and Dawn use this dilemma to pointlessly debate which is better. However, Nando sees how passionate they both are about their respective careers, and decides to give both contests and league battles a shot. As a result of his level-headed behavior and diplomacy, Nando was able to reconcile the two and get them to respect each other.
6 Staravia Evolves Into Staraptor
Evolution is a major deal in the anime as far as story beats are concerned. Ash's Staravia evolving into Staraptor is an example of this, as it evolves at exactly the right time for a come-from-behind victory.
At the Pokering competition, Ash and Staravia are entered in to try and win the competition. He soon sees that his ruthless rival, Paul, has also entered with his Honchkrow. After breezing through the rounds, they are able to meet at the final stage. Though it is a close battle, Ash's Staravia evolves just in time and learns Close Combat, giving them the edge that they needed to ascertain victory.
5 Ash Adopts Paul's Chimchar
This ranks as perhaps one of the most fan beloved moments in the entirety of the Pokemon anime series. Paul and Ash are entered into a tag battle tournament and, for better or for worse, are paired up with one another by sheer luck.
Paul and Ash are two trainers that have entirely different approaches to training. This is showcased in this episode when Paul brutally releases Chimchar. He does so after Chimchar fails to rise to Paul's unrealistic expectations of activating Blaze, Chimchar's special ability that grants bonus damage to all Fire-type moves. Once Paul abandons Chimchar, Ash steps in to replace Paul as Chimchar's trainer, and offers a kindness that makes Chimchar tear up. The audience probably follows suit as it is a genuinely touching moment and sheds a light on the type of abuse that Paul was levying on poor Chimchar.
4 Brock Decides to Become a Doctor
Towards the end of the Diamond and Pearl series, viewers see a few very touching moments from the Sinnoh cast of characters. However, they also see some major life and career decisions being made by some characters. Brock is one such character.
Brock, known for his dependability, knowledge of Pokemon, and his love for the ladies, is only ever considering his career as a Pokemon breeder and as the Gym Leader of Pewter City. In the penultimate episode of the Sinnoh League Victors series, the group returns to Twinleaf town by way of ship, where they meet a gaggle of baby Pokemon that need medical attention. Brock works hard and heals the Pokemon to the best of his abilities and earns the praise of Nurse Joy. She is the one who suggests him to consider a career as a Pokemon Doctor, and he takes this suggestion to heart.
3 Dawn Wins Against May
The Wallace cup occurs during the Pokemon Diamond and Pearl: Battle Dimension installment of the series, and is the stage for the return of a lot of old characters. One of the characters makes a return all the way from Hoenn, and it is none other than May herself.
After many rounds of performing appeals and contest battling, Dawn finds herself facing off against May. After she witnesses May defeating Zoey, Dawn's doubts of her ability to win her second ribbon start to worsen. However, Piplup is able to pull through for Dawn and win against May's Glaceon, and finally she's able to get out of her career rut.
2 Cynthia Trounces Paul
In one of the most satisfying episodes of the entirety of the Pokemon anime, viewers see Paul get absolutely washed by the reigning champion of Sinnoh, Cynthia. When Ash and the gang meet up with the daunting champion, Paul surprises them all by asking Cynthia to battle him, and she accepts without a moment's notice.
What follows is the most comprehensive win of all time on the side of Cynthia. She is able to defeat every single Pokemon of Paul's with only her Garchomp, and even then, Garchomp seemed to not break a sweat at all. This gives Paul a healthy dose of humility and shame, something he sorely needed.
1 Ash Uses Blaze Correctly
The best episode of the Sinnoh series of the Pokemon anime is when Ash is able to defeat Paul. Not only is he able to successfully defeat his rival, he is even able to use what was previously Paul's Chimchar, make use of his ability Blaze, and throw it in Paul's face that his training method is definitely better for the long run.
In the epic face-off, Paul's Electivire and Ash's Infernape fight tooth and nail, but Infernape is able to active Blaze and is able to control it perfectly in just the nick of time. Although Paul had tried to abuse Chimchar into controlling Blaze, Ash was able to ultimately cultivate Blaze's destructive power to his advantage and win his League semi-finals match against Paul.