Boulder Badge

Boulder Badge

Magnet Train Pass

Head to Saffron City and go into the Blue house to the upper left of the large office building. On the second floor talk to the girl and she was say she lost her Doll. Now fly to Vermillion and go into the Pokemon Fan Club above the Gym and talk to the Kid sitting at the middle table. He'll give you the Doll and then as you leave you'll be stopped by Steven to talk about Latios. Now fly back to Saffron and give the Doll back to get the Magnet Train Pass.

Expansion Card

Fly over to Lavender Town and enter the Radio Tower. Talk to the guy by the table in to upper middle and he'll give you the expansion card. Fly to Vermillion and head East on Route 11 until you see the Snorlax. Access your Radio in your Pokegear and turn on the Pokeflute Channel by moving the icon to the top of the globe and then talk to Snorlax.
Snorlax is lvl 50 and although not Legendary has a low capture rate. So get him really low (False Swipe is great for this. It leaves the Pokemon with exactly 1 HP and can be bought in Goldenrod). I'm not a Collector though so I just fainted him so I could get past and continue on playing. Head into Diglett's Cave and work your way through to the other side of Kanto coming out on Route 2. First off, head down to Viridian City just to get it activated on the map. Make sure to talk to Elm's aid in the Gatehouse to get a Sacred Ash. This Med revives ALL Pokemon.

Boulder Badge - Trains and Snorlax

Pewter City Gym

Once you've activated Viridian City go North on Route 2 and go in front of Diglett Cave to get to Pewter City and the next gym. Not much of a puzzle. You can either go around the 2 Trainers or fight them for EXP. Then take on Brock.

BATTLE: Brock
lvl 51 Graveler, lvl 51 Rhyhorn, lvl 53 Omastar, lvl 52 Kabutops & lvl 54 Onix  vs lvl 67 Typhlosion, lvl 57 Lugia, lvl 56 Ampharos & lvl 58 Dragonite
 
Brock has a lot of strong Rock type Pokemon so Grass would do some major damage. Most of his Pokemon are also Dual Type so if you don't have Grass just check the Pokedex to find something that will work. Once you've defeated him you'll get the Boulder Badge and be closer yet to beating the game.

Boulder Badge - Badge Battle