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.
Allister, of course, is one of the eight Gym Leaders you can face in Pokemon Shield when rematching the Champion Cup. Allister still focuses on using Ghost Type Pokemon, having Dusknoir, Chandelure, Cursola, Runerigus, and Gengar when in battle. All of Allister's Pokemon will be between Levels 60-62, and he'll always Gigantamax his Gengar. Because of this, Allister is still weak against Dark Type Pokemon & Attacks. Allister continues to also struggle against Ghost Type Pokemon & Attacks, since Ghost Types are also weak against themselves.
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