HyperSonic

Hypersonic is a 2.1 Extreme Demon mega-collaboration by Dudex, Serponge, Manix648, Vlacc, Rustam, Nasgubb, ZenthicAlpha, Viprin, PanMan, Evasium, Etzer, and Terron. The level is 1 minute and 56 seconds long, and was verified by Combined on February 22nd, 2017. The level was uploaded on Viprin's account. This level is the sequel of Ultrasonic and the prequel of Subsonic. It’s currently #81 on the Official Geometry Dash Demonlist.

Gameplay
Dudex (0-6 %): The level starts off in a mainly blue cube part with all kinds of orbs to hit. It has a mechanical/electric vibe to it. It transitions into the next part via a reverse dash orb.

Serponge (6-13 %): This part is decorated in a very similar way, but with a more "active" background with the use of rotation triggers. This part is played entirely in dual cube form with even more orb timing and some dash orbs at the end.

Manix648 (13-22 %): Starting off with a short quadruple speed ship sequence, you then go into a section with a lot of game-mode changing and flying enemies everywhere. A robot, ball, cube and spider all follow each other in the span of four seconds to which it goes into a normal speed cube and UFO before ending with a robot with two green jump orbs and a dash orb.

Vlacc (22-30 %): The fist half of the part is very colorful with everything switching between different colors constantly, and once again; tons of game-mode changing. The second half is however played in only black and white with a cube, ball and ship; all with tight spaces.

Rustam (30-35 %): Being played in only slow mode, this part's difficulty comes mainly from the hard maneuvering of the UFO and ship in the beginning. This segment is fully colored in purple and contains one of Rustam's high quality skulls. Then comes a ball and a narrow wave before transitioning into the next part.

Nasgubb (35-42 %): Nasgubb is next with a mini spider to start off with tons of crucial timings and orbs to hit. At the end of the part (right before the drop) you briefly change into a robot hitting three dash orbs and a red one in sync to the music before the drop kicks in signaling the next creator's part.

ZenthicAlpha (42-51 %): A triple speed dual starts Zenthic's part with many different game modes being played after each other for 1/4 of the part. After that comes a ship with several size and speed portals placed to mess with the player. Then a short robot follows with a fast paced mini spider being played right after that. It ends with a relatively easy mini UFO into the next section.

Viprin (51-60 %): His entire part is a large ball maze simply requiring the player to remember which orbs to hit and what platforms to land on. The background flashes between a variety of different colors and it spans 1/10 of the entire level.

PanMan (60-70 %): The first half is a dual changing between a cube/robot and a robot/spider switching between triple and quad speed at some points as well. Then you are required to navigate through a moderately tight wave and then a quad speed cube with a bunch of different orbs to be hit.

Evasium (70-80 %): Starting off with a robot flying into a reverse dash orb and a short auto section, you then transform into a UFO with invisible speed portals placed all throughout the section making it all feel very awkward. The same thing is done with the ship which follows as you proceed to do a short segment with a robot and a wave to end it.

Etzer (80-91 %): As you begin as a quad speed spider and wave with very unique effects, you turn into a cube and jump onto a sort of weight scale and into a quadruple speed mini combo portal. A ship sequence follows with usage of the rotation trigger, and then a mini UFO with a cluster of gravity portals to navigate through. A short cube segment and ship sequence follow as you are taken into the final part of the level.

Terron (91-100 %): The entire part is built to be tilted a bit to the right and switches colors to the beat of the song. You start as a narrow wave and then changed into a UFO and a short cube. Then comes a ball and the final ship into a cube portal as the level then ends with a large purple text saying: "HyperSonic verified by Combined."

Trivia

 * This level and its sequel, Subsonic, unlike the other two levels in the "Sonic-series" (Supersonic and Ultrasonic), were uploaded to Viprin's account unlike the other two which were uploaded to ZenthicAlpha's account. This upset some players as they did not feel like it was a true successor to the other two.
 * Due to the many arguments that Hypersonic was generic and not a "Sonic" level, the team who built Hypersonic found a very poor 1.9 styled level with an F-777 song like its predecessors, Supersonic and Ultrasonic, and added the names of the creators in the real Hypersonic in that level to recreate a "Sonic" level.
 * The level used to be a Extreme demon, in the top 50s, but it has since been downgraded to Insane demon.