Throw a ball
You decide to just throw a ball since Zubat are pretty simple. You toss it at the closest one, and it is successfully captured. You continue through the cave, which seems to only be illuminated by glowing stones scattered through the tunnels like miniature neon lamps. You walk over and pick one out of the wall with your fingers, and study it. Suddenly you hear a crashing noise! You go the sight of the noise and see an excavation site! It's littered with Rocket grunts, collecting larger stones, and apparently hunting for a Pokémon known as Clefairy. You also see… Brock! Tied up, unguarded.
Your Options
Ignore the site
Try to sneak to Brock
Bring attention to yourself.
Send a Pokémon to get Brock
Use a Pokémon as a distraction