Name: Juan
City: Sootopolis City
Badge: Rain Badge
Favorite Type: Water
Appearence:
Description: Juan is in charge of the Rain Badge in Pokémon Emerald, and resides in Sootopolis City. His name comes from a common mispronunciation of Juan as Wuan (water). Like his favorite student, Wallace, Juan is an expert on Water-type Pokémon. In Pokémon Emerald, Juan has become the gym leader, as Wallace became the Pokémon League Champion.
In the anime, Juan is the Sootopolis gym leader (and the last gym leader that Ash faces), but Wallace is not mentioned. Juan is also a former Pokémon Contest Champion. As a result, his gym is very stylish, especially compared to the swimming pool of the Cerulean City Gym. He uses five Pokémon in his gym battle with Ash, which lasts two episodes. In the first episode, the battle begins with a double battle. Juan chooses Sealeo and Seaking, and while they defeat Ash's Snorunt, they are beaten by Pikachu and Corphish. In the second episode, the field and positions are switched, and Ash starts with Grovyle, while Juan uses Luvdisc to defeat it. Ash sends out Corphish once more, who defeats Luvdisc, but the crab Pokémon is quickly defeated by Whiscash. Ash defeats Whiscash with his Swellow, and then continues against Juan's best Pokémon: Milotic. Milotic defeats Swellow, but is ultimately defeated by Pikachu, using a full power Thunder attack beneath the water. Juan awards Ash with the Rain Badge and directs the group to the next Pokémon Contest, in Pacifidlog Town.
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Name: Wallace
City: Sootopolis
Badge: Rain Badge
Favorite Type: Water
Appearence:
Description: Wallace is a character in the Pokémon video game series. He was once the Gym Leader of Sootopolis City, in control of the Rain Badge, but was replaced by his mentor, Juan, when he became champion of Hoenn's Elite Four. He is an expert of Water types. In all games, Wallace is the guardian of the Cave of Origin, where deceased Pokémon are resurrected and where the player may catch Groudon and Kyogre in Pokémon Ruby and Sapphire, respectively. His demeanor is similar to that of his mentor's, possessing an affection for lavish beauty and extravagance. Both his names contain the first syllable of their language's words for water ("Wallace" and water, and "Mikuri" and mizu).
In Pokémon Emerald, Wallace plays a far more significant role in the plot line of the game. Wallace is first introduced after the release of Kyogre and Groudon by Team Aqua and Team Magma, respectively. Upon arriving at Sootopolis City, the player speaks with Steven who tells him that someone knows the secret to stopping the natural disasters wrought by the legendary Pokémon. This turns out to be Wallace, who tells him that there is a third legendary pokémon, Rayquaza, that can be found at the Pacifidlog Town. The player then meets Wallace at the Sky Pillar and sends him up to the top of the tower to wake Rayquaza. Rayquaza then comes to Sootopolis City and calms Groudon and Kyogre, and all three legendary Pokémon leave the city. Wallace is then beside the Sootopolis City gym and, unlike in Ruby and Sapphire, Wallace is no longer the gym leader and has turned his position over to his former mentor. His mentor, Juan, uses Water-type Pokémon, much like Wallace did.
Shockingly, Wallace is later found as the Champion of the Elite Four and is a very formidable opponent. He retains his usage of Water-type Pokémon and uses powerful Pokémon in battle: most notably his Milotic, which has astonishing Special Defense; his Tentacruel, which has learned powerful moves like Ice Beam and Hydro Pump; and his Gyarados.
In Pokémon Adventures, he likes Winona, the Fortree City Gym Leader.
Wallace has never appeared in the anime, but it seems that he was planned to judging by some early promo artwork for the anime until the changes in Pokémon Emerald.