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The Lumiose Gym (Japanese: ミアレジム Miare Gym), also known as the Prism Tower (Japanese: プリズムタワー Prism Tower), is the official Gym of Lumiose City. It is based on Electric-type Pokémon. The Gym Leader is Clemont. Trainers who manage to defeat him receive the Voltage Badge. The exterior of the Gym is based on the Eiffel Tower.
In the games
The Lumiose Gym is a high-tech tower known as the Prism Tower. It is initially closed when the player makes his or her first visit to Lumiose City, as the Tower loses power from a blackout. After the player has defeated Team Flare in the Kalos Power Plant, the Prism Tower regains power and is now able to be challenged.
The gym features a series of guarded elevators. Recognition questions about various Pokémon, asked by Bonnie, must be answered correctly to ascend the tower and challenge Clemont. However, before an answer may be deemed correct or incorrect, the respective elevator guard must be defeated.
Once the player gets the question correct, they will move on to the next floor, and the remaining trainers, if not battled, will be inaccessible. Clemont is at the top (6F), after beating him (or before), the player can use the elevator to leave directly.
Trainers are listed in order of the elevator they are guarding.
In the anime
In Clemont and Bonnie's backstory in the anime, Clemont had created a robot called Citroid to cover for him when he found he had little free time due to his duties as a Gym Leader. However, his intended passcode wasn't recognised, so Citroid kicked him and Bonnie out of the Gym. After many failed attempts to reenter the Gym, they gave up. Over the next few weeks, it gained a bad reputation for shocking and violently ejecting challengers for either having less than four badges or losing the Gym Battle.
Unaware of the Gym's reputation as he was a newcomer, Ash went to the Lumiose Gym first in Kalos, Where Dreams and Adventures Begin! since the Santalune Gym was closed at the time. As Ash was about to challenge it, he was denied access as he had no other badges from the Kalos region, resulting in him and Pikachu falling victim to Citroid's ejection policy. Fortunately, the two were saved by Clemont and Bonnie, who had seen them enter the Gym.
The Gym's exterior was featured heavily in Lumiose City Pursuit!, as a rampaging Garchomp climbed it. Ash went up after her to calm her down, but she still caused a fair bit of damage to the tower, to the point where parts were too weak to support even Pikachu's weight.
It later appeared in full in Clemont's Got a Secret!. Ash and Serena discovered that Clemont was the Gym Leader until Citroid took over. After discovering the negative impact Citroid was having on challenger attitudes towards the Gym, Ash and his friends go to the Gym to take it back from Citroid. In the end the gym was passed on to the newly-reprogrammed Citroid while Clemont is traveling.
- This Gym is tied with the Mossdeep Gym in Emerald Version for the highest amount of common Trainers in a Gym, with both having 12. However, in this Gym the player only needs to defeat four of them in order to get to the Gym Leader.
- The multi-colored bricks in the background of the battlefield change color in rhythm to the theme.