Mt. Greyhorn is a stage in The Chronicles of Sonic the Hedgehog: I Am the Future. It is the homeland of the Greyhorn Alliance, a race of anthropomorphic wolves wearing green hoods and cloaks. The stage features two Acts and a Boss for Sonic, while 1 Act, 2 missions and a Boss for the Freedom Fighters. The stage also appears in Sonic Adventure 3: GX as a playable stage, many years before the events of the above mentioned game take place.
Iced Gate is the first Act of Mt. Greyhorn. The stage takes place on a snowy mountain peek. The summits feature multiple constructions made of stones which are built on top of the mountains, where the Greyhorn Alliance resides. It resembles ancient, Chinese temples in the mountains. The stage mostly takes place outside, where the weather is very snowy.
Frosted Mines is the second Act of Mt. Greyhorn. The stage takes place inside the grand structures, where multiple mines are. It is absolutely huge. The stage features coasters, ancient, frozen temples, caves and some exterior parts. It is where the Greyhorn Alliance has been forced to work for eternity.
Boss: Gravitus Decimator
The Gravitus Decimator is fought on a series of mine rails, in a similar way to the previous Bosses. In some parts, the gameplay switches from 3D to 2D perspective.
Freedom Fighters' Story
The Freedom Fighters' stage features one normal Act without a mission, taking place outside, similarly to Iced Gate, and in the interior part, similarly to the Frosted Mines. The stage has the same layout as Sonic's version. However, the player takes a different route. The exterior part of the stage takes place on the snowy mountain peeks of the mountain, outside a series of ancient structures made of rocks. It also features a place with mines and caves, which takes place inside the structures. In the game's story, Rosaline Rose offers to guide Sonic to Mt. Greyhorn.
For their mission, the player, who controls up to 5 different Freedom Fighters, must look for 5 giant Gravitus Pillars, hidden within the stage, to destroy them. The pillars are very large in size so they are hard to miss. Some of them are located inside the mines whereas some of them are located on the exterior part of the stage. After clearing the first mission, the Freedom Fighter must clear the stage once again, this time, by taking a different route and protecting 8 Greyhorn creatures. To do this, the player simultaneously controls all Freedom Fighters and can change a character by inputting a command. The players are attacked by multiple enemies who will also attack at the Greyhorn Alliance. Therefore, the player must quickly defeat them before they lose a member. The creatures will walk together with the pace of the player constantly. However, they are not incompetent and will sometimes attack the enemies themselves, helping at the player. The mission fails when all 8 of them are defeated. At some points, the players must stop and hide behind boulders to take down an army of Gravitus before continuing, while simultaneously protecting the Alliance. In addition, the Third-Person Shooter perspective becomes mandatory at some points of the stage.
Boss: Gravitus Decimator
The Gravitus Decimator is huge. It uses its drills, attached to its arms, to destroy parts of the level and throw them on the player. It is fought on the interior part of the level.