Pokémon Adventures, also known as Pokémon Special, is often presented as the darker alternative to the more kid-friendly Pokémon anime. The manga follows the events of the games, focusing on a different group of trainers in different regions for every arc. Older protagonists do return with new adventures, having aged accordingly as time passes, consistently and realistically.
However, with so many different protagonists, this begs the question: who are the best? In order to narrow it down from the 21 protagonists introduced thus far, we will be limiting ourselves to 10 protagonists from throughout the series, which often presents multiple viewpoint characters as heroes, each one named after the game upon which they're based.
Diamond
Diamond is certainly a more comedic protagonist than his peers. The first Pokémon this food-obsessed trainer trains, fittingly, is a Munchlax. Diamond might not appear as serious as his partner, Pearl, but Diamond's silly and gluttonous nature often disguise his true wit and brilliance. After all, he proves instrumental in stopping Charon's pursuit of capturing all the legendary Pokémon of Sinnoh.
By far one of the goofiest protagonists, Diamond is immediately likable from the start of the Diamond and Pearl arc.
Crystal
Crystal is a Pokémon capturing specialist, hired by Professor Oak for her superb skills. As a child, an encounter with an Arcanine resulted in her arms breaking, which led to her distinctive Pokéball-kicking technique.
What makes Crystal so fascinating is how she can switch between overly enthusiastic to intimidating, particularly when it comes to capturing Pokémon. She's one of Professor Oak's greatest assistants, has won the loyalty of the Hoenn crew with her sheer enthusiasm and was deemed worthy by Suicune to fight the villainous Mask of Ice. Also, she has a couple of different looks, dressing later on like Lyra.
Ruby
Until this point, Pokémon Adventure protagonists came in two main varieties: fun-loving and serious. Ruby, the son of the gym leader Norman, isn't really either of those two. He's prissy, vain and hates fighting. He'd rather engage in Pokémon Contests or design outfits than fight trainers.
What makes Ruby so compelling is just how different he is from other protagonists before and after. Despite wanting to be a Coordinator, Ruby is incredibly accomplished as a trainer, managing to even end up capturing a Celebi at one point!
Sapphire
While Ruby hates fighting, Sapphire lives for fighting. She's a wild card if ever there was one in Pokémon Adventures, rushing headlong into battle at every turn. She's wild and rash but always driven to do the right thing, even managing to convince Ruby to follow the path of justice rather than just always do what he feels like doing.
What's most fascinating about Sapphire is how her relationship with Ruby changes her, especially when we learn about her past in the Omega Ruby and Alpha Sapphire arcs, which delve into her origins as a character.
Red
Red is in many ways the standard protagonist. He's the young boy who wants to go on an adventure, ultimately becoming the central hero who appears more often than any other protagonist in the series.
However, Red lives up to his reputation by constantly excelling beyond all limitations. Red has stood alongside legendary Pokémon, fought fused legendaries, overcame world-ending cataclysms and always emerges on top. He's the hero's hero, always running into conflict to save the day -- sometimes to his own detriment. He's the closest Pokémon Adventures ever comes to a Luffy or Goku.
Green
Green is in many ways the femme fatale of the Pokémon team. She's one of the original three protagonists, which leads to her having a lot of time to craft her own story. The moral ambiguity of Green is what essentially makes her interesting, as she's in part responsible for many of the events that transpire while never quite taking center stage.
Green is fun, mischievous and maybe a few steps removed from an antagonist. But unlike other more morally gray Pokémon Adventures protagonists, she's immediately likable.
Gold
Gold is in many ways cut from the same cloth as Red. He's a hero, through and through, but can be hot-headed and flirty when the occasion doesn't ask for it. However, Gold might be even more accomplished than Red since, on multiple occasions, Gold has saved Red.
He's responsible for essentially saving all of the other protagonists alongside Emerald. He calmed down Arceus, the God of the Pokémon world. He's undeniably one of the most accomplished trainers in the entire Pokémon Adventures saga. That merits his place here.
Silver
While Red and Gold are more accomplished, Silver is undeniably the edgiest of the Pokémon Adventures protagonists, which makes him also one of the more fascinating. Like his game counterpart, Silver is the son of Giovanni. He grew up alongside Green, with the two having an impact on one another.
His arc with Giovanni is arguably one of the most interesting ones in Pokémon Adventures. On top of being just a very compelling character, he's also one of the first to engage in a true redemption arc, which is wonderful to see.
Yellow
Yellow stands apart from the rest of the Pokémon Adventures protagonists. She's a very innocent girl who grew up in Viridian Forest and thus possesses psychic abilities.
Yellow is the first protagonist to be entirely original. She isn't based on a game character, the first of her kind. Her ability to commune with Pokémon spirits makes her even more unique. Also, she saves Red when he ends up in danger thanks to his dumb heroic nature.
Blue
On paper, Blue appears very much like the Pokémon anime's Gary Oak -- a superior rival to the protagonist of the first arc, Red. However, what makes Blue compelling is how he evolves as a character, especially in the Yellow arcs and after.
Blue isn't just some edgelord rival but rather a sophisticated trainer who is very aware and conscious of how the balance of Pokémon and humanity affects the world. He's a very mature character who might be more realistic than the majority of other Pokémon Adventure protagonists.