After some off-screen training

You enter the Cerulean Gym. Your recently evolved Parasect makes short work of Misty's underlings. It's not the most impressive show you could provide, but you think it best to leave the big guns till the big show.

Misty sits atop a lifeguard seat, casually watching you approach. When you stand beneath her, she grins at you so you see her teeth. "I've been waiting."

Your pokemon: Parasect, poor fighter, but possessing spores for beneficial effect. Magneton, with unparalleled resistance, and the much needed damage output to end things quickly. Zapdos, the heaviest hitter you can get, and Voltorb, for when things get dire. You could've gotten more, but you dislike duplicates, so your remaining slots go to Jinx and Seadra.

"I'm ready."

Misty chuckles as she hops down from her perch. She stands too close, pressing her breast into you, "Show me."

Misty strolls over to the battlegrounds and brings out a single pokeball. "To get my badge, all you have to do is defeat this one pokemon. Should you fail, I'll be sure to help you succeed in your next attempt."

This is a trap. You can only hope Misty hadn't planned on you cheating.

You take a deep breath. Your preparation is insane, but you can't help your nervousness. Still, you have to progress. "Okay, Show me what you got!"

Misty grins the widest you've seen, "Suicune."