After completing the Main Story, you can rematch the Champion Cup as many times as you would like. This time around, you can select which opponents will be added to the tournament or if you would prefer a random set of foes. There are twenty-six trainers you can face this time around, including Hop, Leon, Marnie, the eight Gym Leaders, and fifteen Random Pokemon Trainers. Unlike the Random Pokemon Trainers, the Gym Leaders and other Main Characters have stronger Pokemon and each have the ability to Dynamax/Gigantamax one of their Pokemon.
Raihan, of course, is one of the eight Gym Leaders you can face when rematching the Champion Cup. Raihan still focuses on using Dragon Type Pokemon, having Torkoal, Goodra, Turtonator, Flygon, and Duraludon when in battle. All of Raihan's Pokemon will be between Levels 60-62, and he'll always Gigantamax his Duraludon. Because of this, Raihan is still weak against Ice Type and Dragon Type Pokemon & Attacks. Raihan is also weak against Ground Type Pokemon & Attacks, since three of his Pokemon (Torkoal, Turtonator, Duraludon) are types or dual types that are weak against them.
After defeating both the Isle of Armor and Crown Tundra DLC Packages, Raihan's Champion Cup Rematch Pokemon Team will have changed slightly. All of his Pokemon will now be at higher levels.
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