How do you get the 8th gym badge in sienna?

To obtain the 8th gym badge in Sienna, you must first complete the challenges set by the gym leader, which typically involves battling various trainers and overcoming specific puzzles or tasks. After defeating the gym leader, you will be awarded the badge. Make sure your Pokémon team is well-prepared and leveled up to handle the gym leader’s Pokémon effectively. Additionally, check for any specific requirements or quests you might need to complete before challenging the gym.