After much struggling, I found out that flame moves are excellent against Lucario.
I asked Josh about it and he said Lucario was part steel.
Makes total sense.
"...OK. You win." Maylene looked serious as she said it. "That was a tough loss. I learned a lot from it. Please, accept this Gym Badge."
She handed me the Cobble Badge, and I attached it to my trainer card as she explained it.
"I should explain about that official Pokemon League Gym Badge. With it you can use Fly outside of battle. Take this as well." She gave me TM60 (Drain Punch)."
I left the Gym with high hopes, and I run into Dawn.
"Donny! Can you help me? Some Team Galactic goons took my Pokedex away from me. I need your help to get it back. I'll be waiting in front of the warehouse. Please come!"
I watch her run off and then promptly go to the Pokemon Center, and then shopping.
Got 50 Lava cookies for 200 each, which Josh says is a good deal.
Gonna do the warehouse stuff a little later, so sorry about the short update. Did update the trainer card though.