Lunatone is a Rock/Psychic Pokémon introduced in Generation 3. It doesn't evolve into or from any other Pokémon, and has no alternate forms, but it does have a clear relation with Solrock.
Basic info[]
It's a literal moon-shaped rock. Pokémon Colosseum, XD, and Battle Revolution showed it moving around in a circle for an idle animation.
All canon Pokémon are available in Tropes vs. Women in Pokémon Training, including Lunatone. It's mostly unchanged from canon in the final game; however, some beta elements reveal that it was originally going to be the evolved form of a Rock/Ground Pokémon called "Terray".
Also, Lunatone was a candidate for the eventually-scrapped Cosmic type. Had this come to fruition, it would've been Rock/Cosmic. Also, its ability would change to Sturdy, as Cosmic's natural immunity to Ground would make Levitate redundant. (Similar changes were planned for Solrock.) The type chart for a Rock/Cosmic Lunatone?
Under normal battle conditions prior to Generation 6, this Pokémon is...