Since Bea is the fourth Pokemon Gym Leader found in Pokemon Sword, she will definitely give players a run for their Money when in battle. Like Kabu, all of Bea's Pokemon will be fully evolved when you challenge her Pokemon Gym. If that's not difficult enough, she will be the first Gym Leader to battle with four Pokemon. However, Bea can be much more manageable to defeat should you make smart decisions before facing her. For one, if you select Scorbunny as your Starter Pokemon, Bea is much easier to handle. This is because Scorbunny's Evolution Chain actually learns the Flying Type Move Bounce during it's normal Leveling Up Process, and Bea's Fighting Type Pokemon are extremely weak to Flying Type Attacks.
However, even if you don't select Scorbunny to journey through The Galar Region with, Bea can still be handled if you make the correct choices leading up to her Pokemon Gym. One thing you can do in this case is capture Rookidee in any of the routes prior to arriving in Stow-on-Side. Rookidee learns plenty of Flying Type Attacks as they Level Up and Evolve, and, again, Bea's Pokemon are incredibly weak to these type of moves in battle.
But should you not want to start with Scorbunny or capture Rookidee in preparations to facing Bea, you don't actually have to in order to defeat her. Bea's four Pokemon will all be below Level 40, so one could, honestly, train all of their Pokemon to Level 40 or Level 45 and still defeat her. This is incredibly simple to do if you participate in plenty of Max Raid Battles in the Wild Area and stock up on EXP Candy when you do.
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