From Bulbapedia, the community-driven Pokémon encyclopedia.
Mt. Sorbet (Japanese: ソルベラスやま Solbelas Mountain) is a location in Pokémon Ranger: Guardian Signs.
It is located north of the east end of Sophian Road on Sophian Island. It is the home of the legendary bird Articuno. Upon reaching the top of the mountain for the first time, the Pokémon Pinchers will be seen attempting to gain control of Articuno, which then flies off. After completing the game and accepting a mission from Rand, players must chase down the three legendary birds through the sky. Upon catching up with Articuno, it will go down to its home on top of the mountain. There, players must battle it to gain a part of the golden armor. Upon victory players will obtain the Ranger Sign to summon Articuno. Using this Ranger Sign at the summit of Mt. Sorbet will allow players to once again fight the legendary Pokémon. There is an Electivire lithograph covering up a cave on the mountain. The player can break the lithograph and gain access to the cave by beating the Thunder Temple leader's Electivire in a past mission.