Within Pokemon FireRed, there are seven different HMs (Hidden Machines) to obtain during your journey. HMs work a lot like TMs in that they are moves that can be taught to your Pokemon; however, unlike TMs, HMs last forever and even can be used in the overworld. Obtaining all of the HMs will also be vital, since you won't be able to complete the entire Main Story & Post Game without them.
HM06 is none other than the move known as Rock Smash. HM Rock Smash can be obtained from the Elderly Man in the Ember Spa on One Island. HM Rock Smash will allow you to crush smaller rocks blocking certain paths across the Kanto Region.
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