Pokémon Black 2 and White 2 walkthrough, Part Twenty-Eight: Mistralton City
After the grim spectacle that was Chargestone Cave, you've emerged successfully on the outskirts of Mistralton City, home of the sixth Pokémon League gym! Pat yourself on the back. Hopefully you managed to snag an electric-type on your way in, 'cause you may need it to get through the flying-type gym trainers who inhabit this place.
Before you really get into the storyline for this area, it's time to perform the usual item checks. Begin by investigating the Pokémon Center just beyond where you came out, as you may have gone through a ton of Max Repels getting through Chargestone Cave in one piece. Unfortunately, no one else here has any items.
The house next to it makes up for this lack. Inside is a woman who's gaga about TMs, and if you show her enough she'll give you an HP Up. She will give six HP Ups over the course of the game if you can manage to find 90+ TMs. That's a lot of TMs. You can also find an Iron in the trash in her house.
Proceed further into town and you'll be greeted by a familiar face you've never personally met: Professor Juniper. She'll evaluate your Pokedex on the spot and give you a Master Ball, which will catch any pokémon without fail. Save this sucker for a legendary pokémon. Soon after the gym leader, Skyla, will show up and talk about taking Juniper somewhere on a plane. Juniper will then leave for the Celestial Tower, and Skyla will give you the option of following Juniper or getting into a scrap at her gym. Finally, a gym leader who doesn't take off on the competition.
Ignore both possibilities for now and check the house dead ahead. There are no items, but the boy inside says he'll tell you something 'cool' if you come back with the local gym badge. Noted. Head west of here for the airport; a woman just inside the terminal will give you a Sharp Beak, and a maid by the counter will give you a Heart Scale if you bring her ten Sweet Hearts, obtained via the C-Gear's Feeling Check. A man in the very back will give you Net Balls if you bring him a psychic- or flying-type pokémon to retrieve some packages.
(Note: Despite how he sounds, the pilot in here won't give you anything for showing him the Ace Pilot Medal. Jerk.)
Leave the airport and head out onto the runway. Check the space between the grey and orange planes for a hidden Flying Gem. Check the south-east end of the airstrip for TM58 Sky Drop beside a bulky plane. At the end of the runway you'll see a man who will ask you for Mulch from Hidden Grottos, who will buy it at a premium. Run behind him and check between the south-west greenhouses for a Max Repel.
That's all for Mistralton City. You have two choices: challenge the gym or going looking for Professor Juniper. For preparedness' sake we'll go looking for Professor Juniper next, as she has a fantastic item that will make the gym a whole lot easier.