Rock Tunnel can be exhausting, so you may need to bring a few extra items. Potions are a must with fifteen Trainers wandering around in the darkness, and Repels and Escape Ropes are also helpful. If any of your Pokémon know the Dig move, they can return you to the tunnel's entrance at any time. Be aware that Flash is needed to illuminate the Rock Tunnel.
Lavender is a tiny, quiet town, but it is not without its own unique landmarks. The most well-known is Pokémon Tower, while the Lavender Volunteer Pokémon House and the Name Rater are also found here. The Poké Mart in the southeast offers some new items, like Revives and Great Balls.
The house on the south side of town belongs to the Name Rater. This man judges your Pokémon's nicknames, and gives you the chance to change them. His service is free, so you can change nicknames as often as you would like.
Kindly old Mr. Fuji, head of the Lavender Volunteer Pokémon House, has gone missing. His disappearance may have some connection to the recent paranormal activity occurring in nearby Pokémon Tower. However, besides keeping an eye open for clues, there's nothing that can be done about it right now.
You can't battle them if you don't know what they are!
Pokémon Tower, where departed Pokémon are laid to rest, appears to be the source of the town's problems. Having a connection to the spirit world, most wild Pokémon found inside are Ghosts. Blue is on the tower's second floor, but you may decide to delay that battle by avoiding the tower for now. The spirit world's influence strengthens above the second floor, where ghosts and possessed Channelers are commonplace. But without a Silph Scope, you won't be able to climb to the tower's top floor.
Most ghosts inside the tower are truly Pokémon in disguise that can be battled or captured after obtaining the Silph Scope. Gastly and Haunter are two of the only three Ghosts in the game, so it's worthwhile to track them down. The one true ghost in the tower blocks access to the final floor, but since you can't do anything but run from it, it's best to ignore it for now. However, there are rumors of a Silph Scope prototype in Celadon City, so pack up and head west.
Celadon City lies off to the west, but Saffron City stands in the way. No one is currently allowed through the gate, so enter the building to the north and take the Underground Path that runs underneath Saffron. Remember to use the Itemfinder in the tunnel to search for lost valuables. The tunnel emerges on Route 7.