Route 10 is a small zone that leads to Rock Tunnel. The area here contains one of the very few Electric Pokemon available to you at this point in the game, so stick around for a while.
Hopefully, you made sure to pick up HM05 Flash from one of Professor Oak's aides in Route 2 before going into the cave, 'cause it's about to get really dark for you.
Going through Rock Tunnel may seem like a roundabout route, but it's the only way, as there is a Snorlax blocking Route 12 and the thirsty officer blocking Saffron City will not let the player in.
Inside the Pokécenter south of this area you will find one of Oak's Aides. Talk to him and, if you have complete data on 20 types of Pokémon, he will reward you with an Everstone, which can be held by a Pokémon to prevent it from evolving.
As a side note, remember to return to this area once you have the ability to Surf, as the waters here will lead you into the Power Plant, and a powerful Legendary Pokemon!
|FireRed||Level||Encounter Rate||LeafGreen||Level||Encounter Rate|
|1||Heidi||Pikachu 20||Clefairy 20||400|
|1||Carol||Pidgey 21||Pidgeotto 21||420|
|2||Clark||Geodude 21||Onix 21||756|
|3||Trent||Onix 19||Graveler 19||684|
|4||Herman||Cubone 20||Slowpoke 20||960|
- Persim Berry (hidden in mid-southeast corner under PokeCenter)
- Cheri Berry (hidden a few spaces to the left behind Picnicker Heidi near the PokeCenter)
- Nanab Berry (hidden in northeastern corner after coming out of Rock Tunnels southern entrance)
- Super Potion (hidden just west of the pokecenter, accessible by using cut on a tree)
- Everstone (Given to you in the pokecenter by Oak's aid when you catch 20 or more pokemon)
Voltorb's only offensive Electric move is Spark at level 21, so it will need further TM's to make it strong.
It's a good idea to pick up the TM from Rocket Game Corner in Celadon City if you plan on making Voltorb your primary Electric type. Voltorb evolves into Electrode at Level 30.