Pokemon Co. has put together a new feature on Pokemon Masters EX that's meant to help players out with the Champion Stadium. If you're looking for a few tips or tricks, you can check out a blurb from the feature below, and then click over for the full piece.
The Champion Stadium will only have the Normal difficulty available when you first unlock it. This difficulty can be comfortably cleared for completion rewards even by lower-level sync pairs. Once you've had your first taste of the action, you'll unlock Hard difficulty. Lv. 125 sync pairs are recommended for this difficulty. You can face challenging battles here once per week for great rewards, so read on for tips about taking on the toughest battles the Champion Stadium has to offer.