Terrakion

Rock

As one of Rock's most flexible offensive Pokemon, Terrakion provides an invaluable presence on Rock teams and contributes to the success of many teams. Its unique Rock and Fighting STAB combination supplemented by powerful attacks in Close Combat and Stone Edge provides useful coverage and makes it difficult to wall. In particular, Fighting STAB is extremely useful for beating Steel-types, which most of Terrakion's offensive teammates will have trouble breaking through. With base 108 Speed, Terrakion is one of the fastest Rock-types available and effectively takes advantage of this by acting as an ideal wallbreaker and revenge killer. However, Terrakion is still limited in what it can do, as both of its main STAB attacks have drawbacks, and although it provides great STAB coverage, it doesn't add much defensive synergy to the team. Despite this, it has the ability to fit what most Rock teams need and can improve almost any Rock team.

Fighting

With useful STAB coverage, good Speed, and a Flying neutrality, Terrakion fits well on Fighting teams, which tend to be offensively inclined. Terrakion's great Speed tier lets it outspeed most common Choice Scarf Pokemon, most notably Victini and Togekiss. Although it might not have the bulk to take too many hits, Terrakion has enough natural bulk to check Flying-types that the team might struggle with if it needs to and thus eases pressure off its teammates. Mega Pinsir is a great example of this, as Terrakion is Fighting's only real check for it. However, since Terrakion typically holds a Choice Scarf in order to revenge kill Pokemon more easily, it may find itself lacking power against defensive Pokemon, such as Skarmory, Hippowdon, and Gliscor, so it relies on its teammates to help weaken these walls first. Late-game, however, is when Terrakion shines and shows why most Fighting teams don't go without it.