The Lumiose Gym is a high-tech tower known as the Prism Tower. It is initially inaccessible when the player first reaches Lumiose City as it and much of the rest of the city have lost power due to a blackout. After the player has defeated Team Flare in the Kalos Power Plant, power will be fully restored to the city and the player will be able to challenge Prism Tower.
The Gym features groups of elevators guarded by the Gym's Trainers on several floors. On each floor before the sixth (where Clemont is), Bonnie will quiz the player about a Pokémon's silhouette as a multiple choice question, and the player must choose the elevator corresponding to the correct answer. The player must battle the Trainer guarding the elevator they have chosen before they can enter the elevator and know whether they have chosen correctly. If the player has chosen correctly, the elevator will ascend to the next floor, but if they have chosen wrongly, they will have to try another elevator.
Any Trainers the player did not battle before moving to the next floor will not be battleable if the player returns to that floor. Any elevator the player used to ascend to a floor can be used to either return to the previous floor or directly to the first floor.
Appearance
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Prism Tower appears as a playable stage in Super Smash Bros. for Nintendo 3DS, serving as a hallmark for Lumiose City. Matches begin on the ground level of the tower in front of the building, and players must climb the tower by securing footholds (such as moving platforms). As the stage ascends, the background scenery changes to a different time of day.
In the anime
In Clemont and Bonnie's backstory in the anime, Clemont had created a robot called Clembot 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 Clembot 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 Clembot'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 Clembot took over. After discovering the negative impact Clembot was having on challenger attitudes towards the Gym, Ash and his friends go to the Gym to take it back from Clembot. In the end, the Gym was passed on to the newly-reprogrammed Clembot while Clemont is traveling.
It reappeared in XY063, when Clemont began his training for his battle with Ash, bringing his Pokemon from the Gym to his active party. The Gym will be the site of the gym battle in XY067.
Trivia
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.
