Sparing a training montage, your Pokemon are all decently leveled now. Your Pikachu and Mankey were probably on par with Brock's Pokemon by now and your Kakuna was close to evolving.
The first and only trainer besides Brock challenges you, spitting out nonsense about light years and what not. With Mankey out, his Geodude is no problem. His Sandshrew, however...
"Go, Kakuna," you say. Your bug Pokemon is intimidated, but that will not stop you nor it.
"Poison Sting it!" you exclaim. In a rapid motion, your Kakuna shoots out a poisonous needle. It poisons the Sandshrew, but it seems to have been rather ineffective as the Sandshrew stands firmly. The battle is a long one, as attacks are met, each and every one doing minimal damage. In the end, however, your Kakuna stands victorious and just like that, it evolves in front of you.
"An interesting trainer," Brock states, looking at you. He beckons for you to come up. "In my years here, I've never seen a trainer so confident yet so masterful. Let's see if you're even better than the trainer who just beat me!" That must have been Blue.
You're first Pokemon is Mankey who has the distinct advantage against his Geodude.
"Low Kick!" you shout. In a quick sweep, your Mankey flips over the boulder-like Pokemon. With the free opportunity, you command it to use Karate Chop. With lightning speed, your Mankey knocks out the Geodude.
"Alright, Onix, do your thing," Brock said, grinning.
"Mankey, Low Kick!" you say. Mankey does a similar motion as before, but this time it seems to take little effect.
"Onix, Rock Tomb!" Brock commands. A shower of stones appear, all falling on top of Mankey. It's speed is severely hindered and it doesn't seem like it could take more than one hit.
"Alright, come back! Go Beedrill!" you exclaim. Brock is mildly confused, but he continues nonetheless.
"Beedrill, String Shot!" you exclaim. As it did like a Kakuna, it shoots out a string-like goo that wraps around the snake-like Pokemon. Onix retaliates with a Rock Tomb, but your Beedrill is able to take the hit.
"Come back, Beedrill! Go, Mankey!" you command.
The Onix struggles to move as your Mankey Low Kick's the giant Pokemon again, knocking it down. And like before, the Rock-type is taken down with a Karate Chop.
"Looked like you were on the ropes there," he tells you. "You have great skill to think up a strategy so easily and so quickly. Here take the badge and the TM for Rock Tomb. He waves you a goodbye and you leave the gym with your first major victory in hand.
But there she is. You can see Blue up ahead.
