James' Yamask is a Pokémon James caught in BW025 while he, along with Jessie and Meowth, were searching for their boss Giovanni after he disbanded Team Rocket. Its battle strength can't be gauged very well as it makes only intermittent appearances.
While searching for their Boss, James caught Yamask after feeding it, it then happily accepted becoming James' Pokémon.
In Scare at the Litwick Mansion!, three devious Litwick tricked Yamask and kidnapped it along with Meowth, Iris' Axew, and Ash's Pikachu but the Litwick and their Lampent leader were defeated by them.
In Gotta Catch A Roggenrola!, Yamask was used to take down the Roggenrola, but was taken down by the Roggenrola's Flash Cannon attacks.
In Crisis at Chargestone Cave! Yamask was used alongside Woobat to take down Ash's Pikachu and Bianca'a Minccino with Night Shade but it got hit with Thunderbolt and Swift. It later tried to take down Cilan's newly evolved Crustle with Shadow Ball, but Crustle's Rock Wrecker intercepted Yamask's attack, forcing the Rockets to retreat.
In A Restoration Confrontation! (Part 1), Yamask was used to battle a newly restored Tirtuoga that escaped from Dr. Zager's helicopter. In Part 2, Yamask was used again to take down Ash's Pikachu and Cilan's Pansage in order to prevent them from getting the newly evolved Carracosta to safety, but the latter got beaten by Carracosta's Ancient Power, forcing the Rockets to retreat.
Yamask, like Woobat was used frequently in Team Rocket's Unova operations in the Black & White series as well as the Rival Destinies series finale as James' main Pokémon. This made Yamask very strong in battles against Ash and friends, although it is not used that much as Woobat.
After TR's defeat in Rival Destinies' series finale, and the temporary retreat back to Kanto, Jessie catches a female Frillish and James catches an Amoonguss while going back to Unova. Since then, Yamask has not been used that much as Amoonguss has.
It made it's return to Adventures in Unova in The Pokémon Harbor Patrol! were Yamask was used once again alongside Woobat to weaken Ash's Pikachu but Team Rocket quickly called back their Pokémon and made a hasty retreat.
It was also used to fight off Team Plasma's controlled Pokémon in What Lies Beyond Truth and Ideals!.
|Haze||A Fishing Connoisseur in a Fishy Competition!|
|Shadow Ball||Scare at the Litwick Mansion!|
|Night Shade||The Dragon Master's Path!|
|Will-O-Wisp||A Restoration Confrontation! (Part 2)|
|+ indicates this Pokémon used this move recently.*|
- indicates this Pokémon normally can't use this move.
- James' Yamask is the first Ghost Pokémon owned by a main character.
- Unlike James' past Pokémon, Victreebel, Cacnea, and Carnivine, Yamask does not show any kind of affection when it is sent out.
- Similar to how Ash's Oshawott can use its Scalchop as a shield, James' Yamask can use its mask as a shield to defend its ally in battle.
- Similar to Jessie's Seviper, Yamask can use Haze in order to shroud Team Rocket in a cloud in order to prevent their cover from being blown.