Unknown (アンノウン An'nōn?), also called F-Zone or Point-W, is a Zone in Sonic Rush. It is the eighth Zone for both Sonic and Blaze, and the final regular Zone in the game. Unlike most other Zones in Sonic Rush, Unknown consists only of a Boss Act devoted to the local boss. It takes place amidst the falling debrie of a collapsing spacecraft.
While Unknown is set on a metal platform in outer space, the background continually changes based on the player's progress throughout the battle as the platform descends closer to the planet's atmosphere. At the beginning, the moon is visible in the background and at the end, the planet can be seen.
Having taken it upon himself to defeat Eggman Nega on behalf of Blaze, who is too injured after her last battle to fight, Sonic travels to Unknown with Tails. There, Sonic engages Eggman Nega and his Egg King mech in battle as they fall towards the planet below. At the end of the fight, with the Egg King on its last legs, Eggman Nega tries to crush Sonic by ramming the Egg King into the plaform Sonic stands on. Despite this, Sonic manages to bring the Egg King down in a large explosion. After landing on the ground, Sonic looks over the wreckage of the Egg King and comments that it "was easy". Sonic is then met by Tails, some Animals, and his other friends. As Blaze and Cream celebrate, Tails notices that Sonic has something on his mind, but Sonic calmly assures him that it is nothing. Knuckles then appears, telling Sonic to "split now", having noticed amy's arrival as she calls out for Sonic. Taking his leave, Sonic runs away while Amy chases after him with her Piko Piko Hammer pulled out. Tails then comments that "At least everything is back to normal".
In an effort to rescue her friend, Cream, who has been kidnapped by Dr. Eggman, Blaze has complied to Eggman's demands and travels to Unknown to face Eggman alone. There, Blaze engages Eggman and his Egg King mech in battle as they fall towards the planet below. At the end of the fight, with the Egg King on its last legs, Eggman tries to end Sonic by ramming the Egg King into the plaform Blaze stands on. Despite this, Blaze manages to bring the Egg King down in a large explosion. After landing on the ground, Blaze looks over the Egg King's wreckage, ready for what it has come down to. Blaze then begins searching through the wreckage while calling out for Cream. However, Blaze then notices Cream falling down from the sky, calling out to her. Landing in Blaze's arms, Cream thanks Blaze for rescuing her. Blaze tells Cream not to mention it though, because they are friends.
In Sonic's version of Unknown, if the player has not collected all the Chaos Emeralds, Eggman Nega will appear with a message: "Collect all the Chaos Emeralds." If the player has all the Emeralds, but has not finished Blaze's story, Eggman Nega will tell the player to finish Blaze's story.
The boss of Unknown, and the only playable section of this stage, is the Egg King, a behemoth of a robot piloted by Eggman and Eggman Nega respectively. It can be fought immediately after entering Unknown.
In battle, the Egg King attacks with shockwave-inducing slams, laser beams and drones. To damage the Egg King, the player must attack its fists or head when they are accessible. In the latter case, the player must climb the Egg King's arms to reach its head. As the battle progresses, however, its attacks get more relentless. After enough hits, the Egg King will try three last attacks which must be dodged before hitting its head for the last time.
- The background music for Unknown, "Bomber Barbara," has parts that are derived from "Teknopathetic," a song from Jet Set Radio Future in the Jet Set Radio series, another highly praised Sega franchise. This is probably due to the fact that both games' soundtracks were written by Sega composer Hideki Naganuma.
- The colors on Eggman's mecha correspond to Blaze's color scheme (purple-ish pink), while the colors on Eggman Nega's mecha correspond to Sonic's color scheme (red, white, and blue).
|"Bomber Barbara"||Hideki Naganuma||2:08|
|"Bomber Barbara (Part 2)"||Hideki Naganuma||0:39|