Cheren is a childhood friend of the player who, like the player, lives in the starting town of Nuvema Town. While he holds a greater knowledge in Pokémon than his friends and tends to offer the player advice during the course of their journey, his comments are often witty and intellectual. He also misunderstands Bianca's humor often, to her dismay. Whilst Professor Juniper describes him as being very honest, she also remarks that he can be 'a little difficult'; his impatience in particular is often seen throughout the earlier stages of his journey. He is also described as being quite judgmental by Alder.
In keeping with the theme of truth and ideals often seen in Black and White, Cheren represents those who pursue ideals—more precisely, as N pointed out in Chargestone Cave, the ideal of strength. His goal is to become the Champion and always strives to become stronger- yet the first time that Alder asked him why he strives to become stronger, he was quite unsure of his reasons. He then starts to ponder to himself how to do so—something that Alder said he used to do with his partner Pokémon as well—and what exactly it means to be strong. Alder also remarked that Cheren is a lot like Marshal.
Like the player and Bianca, Cheren receives a starter Pokémon as a gift from Professor Juniper at the start of the game. He always chooses the starter with a type advantage over the player's starter. The player will encounter and battle him several times throughout the game. After the main storyline, Cheren can be found inside Victory Road where he can be battled once a day.
"I've finally become a Trainer... Everything starts from here!"
After defeat
"Ah! So that's a Pokémon battle!"
After losing
"I made a strange blunder in my first battle, but this feeling I have... I'm finally a Trainer. But first, we'd better go apologize to your mother about this messed-up room."
After winning
"This feeling... Finally, I'm a Trainer. On top of that, we'd better go apologize to your mother about this room."
Cheren appears as a supporting character in Pokémon Adventures.
In the Be a Master!! Pokémon BW manga
Cheren is friends with both Monta and Bianca, he is very knowledgable about Pokémon, which Monta dislikes. Anywhere Monta slips up he won't hesitate to tell him the right way. He first appears with Bianca when Monta is attempting to capture a wildPatrat and Watchog. Monta is just about to capture the Watchog which Cheren tells him that it is not the right way. He explains to Monta to remember that when two Pokémon come out at the same time, one should knock out the one they don't want before they can get the one that they do want. Cheren suddenly decides for all of them to take their Pokémon journey together, which a man on his bike overhears. He starts insult them making him and Monta angry.
He uses Tepig in a Double Battle with Monta's Snivy against a Bike Gang King's Braviary, it looks like they were about to lose, but they uses a combination attack which Cheren thinks of, fainting Braviary. Cheren battles Monta in PBW02 using his Tepig, Pansage and Basculin against Monta's Snivy, Panpour and Roggenrola. He starts off with a lecture about triple battles. With his great knowledge of triple battles he gives Monta a hard time, but is eventually defeated.
Cheren's Tepig is well trained and has a type advantage over Monta's Snivy. It was first used in a Double Battle with Snivy against the Bike Gang King's Braviary. After Snivy tries a Vine Whip which hardly does any damage, he goes in for a fire attack which hardly does any damage too. Tepig is then sent flying with Peck. It goes in with a Fire Pledge with Grass Pledge creating the combination needed to defeat Braviary.
It battles Monta in PBW02 with Pansage and Basculin against Monta's Snivy, Panpour and Roggenrola. It starts off with an Ember on Snivy, before taking a hit for Basculin by switching places with it, not hurting it much. But seconds later, Panpour uses Surf fainting it.
Cheren's Basculin was first seen in a battle against Monta's Snivy, Panpour and Roggenrola with Tepig and Pansage. It is about to get hit by Snivy's Vine Whip but switches places with Tepig. It then gets hit by Panpour's Surf which does not do much damage. But along with Pansage is defeated by a powerful Rock Slide from Roggenrola, fainting it.
None of Basculin's moves are known.
In the Pokémon Pocket Monsters manga
Cheren makes a brief appearance in the very first chapter of Pocket Monsters BW where he along with Black and Bianca go to Professor Juniper's lab to get their first Pokémon.
Cheren is the only named rival who keeps his Japanese name.
Cheren is the first rival to become a Gym Leader within a generation. Blue was the player's rival in Generation I and III and was a Gym Leader in Generation II and IV.
Cheren is the only Gym Leader who gives out a badge previously given out by another Gym Leader, who doesn't give the badge away in the same Gym as the previous leader.
