Go underground and start diging
thunder stone
thunder stone
the Pokemon are pikachu and evee to jolteon and that is all
Underground use the Explorer Kit.
You can get the thunder stone by going underground and digging for it in Pokemon diamond/pearl ( the thunder stone , fire stone, water stone, and the leaf stone is very rare, so good luck!).
Thunder stone =Jolteon Water stone = Vaporeon.Fire stone = Flareon.
if u have an eevee use a thunder stone to evolve it into a jolteon
the Pokemon that evolve with the help of a thunder stone are : pikachu +thunder stone = raichu, or eevee + thunder stone = jolteon.
well you can evolve eevee with a thunder stone,a water stone,a fire stone hope i helped
It is in Sunnyshore City near the lighthouse.
The level of your pikachu doesn't matter, because to make it evolve you use a thunder stone on it. i hope that answers your question. You can get a thunder stone underground.
There are only two Pokemon(without the National Pokedex).They are Pickachu (into Raichu) and Eevee (into Jolteon).