Rock Smash is a valuable move in Pokmon Ruby that allows the user to break boulders, which can block paths and access to new areas. To obtain Rock Smash in Pokmon Ruby, the player must first defeat the Gym Leader, Roxanne, in Rustboro City. After defeating Roxanne, the player will receive the TM for Rock Smash, which can then be taught to any Pokmon that can learn it.
Rock Smash is an important move for several reasons. First, it allows the player to break boulders that block paths, which can open up new areas to explore. Second, Rock Smash can be used to weaken Rock-type Pokmon, which are common in the early game. Finally, Rock Smash can be used to damage Pokmon that are hiding behind barriers, such as Geodude and Graveler.