Well here we are Bulbasaur. Pewter city, home to our first gym. Dante walked inside and saw his opponent to come. Dante studied the pokedex entry for Bulbasaur as he walked in. Turns out they know this move called vine whip, strong against rock and ground types. This gym should be a piece of cake. Oh how wrong Dante was. Flint welcomed him in and Dante asked.
"So do I just battle you or am I missing something?" It was a bit rude in some sense but Dante was genuinely honest and confused. Flint reassured him
"Yes, don't worry you don't have to be embarrassed. You'd be surprised how many trainers ask me this."
Relieved, Dante let out a breath of relief. Flint continued.
"Here's how we're going to do this. We both choose one Pokemon and the first one that faints, loses the match. Let's head up here to the area."
A rocky battle area is seen in the gym a little further up.
"Now, let's get this started. Go Golem!"
A strong and sturdy golem is released from its pokeball. Dante started panicking inside, this thing was way bigger than a rattatta. There was no way Bulbasaur could beat it. Maybe if it got lucky. Here goes nothing.
"Go Bulbasaur!" And out came Bulbasaur to the field from Dante's side slowly. He reassured his new friend.
"You can do this Bulbasaur. I have my faith in you!" 
The gym battle starts.
"Golem use roll out!" A massive boulder came tumbling towards Bulbasaur.
"Hurry Bulbasaur get out of the way using vine whip!" The quick descision saved the Bulbasaur from a fast battle as it roped itself out of the way. The unfortunate golem went tumbling into another rock on the field and obliterated it as it landed. 
"Bulbasaur use vine whip hurry!" Two long vines started whipping the golem from afar. 
"Golem don't let it get to you, use rock throw!" The golem picked up the remains of the boulder and chucked it at the Bulbasaur. It whipped away a good amount but was hit hard by a barrage of rocks barely holding on. The golem was too strong for him but it was slow and heavy. Dante had an idea. He waited for the golem to move. 
"Golem, rollout now!" The golem started to make its running start before
"Hurry Bulbasaur, Trip it now using vine whip!" vines started wrapping around its stubby legs and Golem tripped out of position for a roll out and into another boulder. Golem couldn't move much, it was incapacitated.
"I can't believe that worked. Good job Bulbasaur!" Dante exclaimed.
"Return Golem!" The poor incapacitated golem was returned to its ball. Flint walks up to Dante.
"Well congratulations kid. I think you deserve your first badge." He presents the Boulder badge to Dante.
"Treat it well. You deserve it."
Dante picked up his first badge and kept it safe in a small badge case (which I forgot to mention at pallet town whoops).
"Thank you. I can't express how this feels right now."
Flint smiled
"You don't have to worry. Have fun on your journey kid. I'm sure you'll go far."
Dante thanked Flint for the battle and went off to the Pokemon center to heal his Bulbasaur. Still no sight of the mysterious man.