>In Nimbasa City, you will discover the Ferris Wheel. Outside the Ferris Wheel, after you have beaten the Nimbasa Gym, you will find a new trainer outside it every now and then. They will challenge you to a battle and then go up on the Ferris Wheel with you.. Sometimes, there won't be a trainer to battle, but it will be an important character such as Bianca, Cheren or your rival. The people you face change depending on your gender and the season
>When you have defeated the Elite Four, you will encounter your rival on Tuesday, Bianca on Wednesday, N on Friday and Cheren on Saturday
Cheren does appear at the Ferris Wheel; you simply went there on a Saturday.
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