Hammerlocke Stadium is the largest building in the city and is the site at which the eighth installment in the Galarregion's Gym Challenge takes place. It is located in the central part of the city, past the center Pokémon Center.
In addition to the standard Poké Mart and uniform shop, Hammerlocke Stadium's lobby also has an elevator to Macro Cosmos's underground Energy Plant, which provides access to the Tower Summit at the top of the stadium, where the player battles Eternatus during the climax of Pokémon Sword and Shield.
Gym Challenge
Gym mission
During the Gym mission, the player is required to fight Double Battles against three Gym Trainers at Hammerlocke vault, each of whom specializes in a specific weather condition.
While pursuing Sordward and Shielbert, the brothers will use their stock of Wishing Stars to force multiple Pokémon from the Stadium to Dynamax against their will, causing them to rampage in the Stadium. The player will face a Haxorus with their party while Hop, Piers, and Raihan handle the rest.
Hammerlocke Stadium was first mentioned, although not by name, in Flash of the Titans!, where Lance revealed he had once trained there. He had also been impressed by the Gym's uniform and its rich history, and had thus decided to use it as the basis of his own current outfit.
The Gym was mentioned again in JN027 as Raihan made his anime debut.