When challenging the Galarian Star Tournament, you will eventually have the choice between seventeen different trainers to Pair with or face off against. No matter whether you pair with them or they oppose you, their Pokemon teams will never change. One of these seventeen trainers is none other than your Rival, Hop, and his team will vary depending on the version you are playing and what Starter Pokemon you originally selected (just like during the Main Story). No matter what, Hop will always bring into battle Level 69 Dubwool, Level 70 Zacian/Zamazenta (depending on your version of the game) in their Crowned Hero Form, and Level 70 Rillaboom/Cinderace/Inteleon (depending on your Starter Pokemon) that will be able to Gigantamax.
No matter what Pokemon you use, it would be smart to have higher leveled Pokemon with Pokemon Attacks of varying types. Hop's Dubwool is only weak to Fighting Type Moves, so it would be wise to have at least one on one of your three Pokemon. Whether Hop has either Zacian or Zamazenta, both will be weak against Ground Type Moves and Fire Type Moves since they will be part Steel Types because of their Crowned Forms. Again, it would be wise to have at least one of those attacks. As for his final Pokemon, it all depends what Pokemon he has: Inteleon is weak against Electric Type Moves and Grass Type Moves, Rillaboom is weak against Fire Type Moves and Flying Type Moves; and Cinderace is weak against Water Type Moves and Ground Type Moves.
Will all of that said, it really doesn't matter what Pokemon you use as long as they are at incredibly high levels. As long as your Pokemon are weak to certain other Pokemon Attacks, a Level 90-100 Pokemon will usually handle any Level 70 Pokemon with ease.
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