Gamma

Gamma is a 2.1 Extreme Demon mega-collaboration created by Angryboy, Lemons, Metalface221, MindCap, Pennutoh, Lithifusion, Mactanow, Djoxy, HequinoX, and iNighti, and verified by Sunix. A coin update and LDM was later added to the level, the update being verified by Technical. It is currently #4 on the Official Geometry Dash Demon List, above Sonic Wave (#5) and below Plasma Pulse Finale (#3).

History
Gamma was started by MindCap in June 2017 when several creators such as Mactanow and Metalface221 made their parts (at that time, WOOGI1411 was planned to be featured in the mega-collaboration as well). Then, DollarC uploaded a new video for a preview of Gamma (with MindCap's permission) and it showed that WOOGI1411's part would be replaced with EndLevel for an unknown reason.

After two months, the level was nearly finished and Metalface221 released the full level showcase in August 2017. Now that the full level was released, the Gamma team would have to look for a verifier. At first, Metalface221 was set to verify this level. However, he eventually dropped it for unknown reasons.

Eventually, Sunix was chosen to verify Gamma in November 2017. He started making progress quickly, getting a record of 44% on November 11. 8 days later, he achieved a new record of 74%, making it to Mactanow's part.

After that, he started streaming Gamma on Twitch and eventually got a record of 90% then 94%, both fails in Djoxy's part. A month later on December 9, 2017, Sunix finally verified Gamma after over 10,000 attempts. In his video, he verified it on his account, but he uploaded it on MindCap's account using a verify hack because he didn't want to beat it again.

Soon, there were plans for an unnerfed version of Gamma to make it even harder, but it was cancelled for unknown reasons. So MindCap instead gave Gamma an LDM and Coins Update, which was verified by Technical, who also happened to be making fast progress on the level at that time.

Gameplay

 * 0-8% (Angryboy): The level begins with a jump pad taking the player into a chunk of gameplay centered around timing with jump orbs and jumps as a mini cube. Jump orbs come in all varieties and requires hard timings to hit correctly. Halfway through, the cube turns big and goes into double speed for a short period, then comes a mini spider with tight spaces to pass through as well as a few orbs to hit. The part ends with a reverse dash orb taking the player to a black screen as the words "Good Luck..." shows up.
 * 9-19% (Lemons): This part is a lot more hectic than Angryboy's part and features several portal changes throughout. It starts with a cube section and swiftly turns into a tiny mini ball, and then back to cube form. This short cube section leads into a spider with two jump orbs leading back to another cube, this time a bit longer. After this confusing cube section comes a short mini straight fly into a sync-based mini wave. A dual mini cube comes next with a few jumps, and then a short ship and spider followed by each other. Near the end is a tight wave segment with multiple size changes, and finally a robot with one blue jump orb and two reverse dash orbs taking the player to the next part.
 * 20-33% (Metalface221): As the gameplay from Lemons' part seems to go on, a teleportation portal takes the player to a completely different part started off with a long, very fast memory UFO with size/gravity portals cluttering up the entire part as well as a few orbs here and there. After this UFO comes a wave with a few size portals to adapt to, and then a swing copter through a dark passageway leading to the final upside-down straight fly which needs to be times so that the mini cube on top will jump at the right moments as well. Successfully doing so will take the player onward to the host's part.
 * 33-40% (MindCap): Here, the gameplay will start with a slow ship section requiring precise clicks in order to pass through the many small straight fly bursts. The ship then turns into a mini wave with clicks that need to be just as, if not preciser than the ship before it. The wave finishes off with a triple speed portal taking the player into a reverse mini UFO which will require some spamming from the player as well as remembering the invisible gravity portals found here. The part then ends with a fast straight fly into an invisible teleportation portal.
 * 41-49% (Pennutoh): This section was designed by Mactanow, but the layout by Pennutoh is as follows: Beginning with a bit of straight fly and a red jump orb jump, the layout switches gravity many times through the ball, UFO and cube gameplay. More straight flying and a difficult mini wave section follow, with precise timing. After transitioning through all that, one last mini wave section leads you to finish this section, and quickly cuts off dark as it leads to Lithifusion's part.
 * 50-62% (Lithifusion): This part starts with a series of dots, saying, "Go." Quickly, you will transition to an incredibly fast dual section with Killbot-styled effects, controlling a ship through one-block spaces, then from both mini and regular waves, until reaching incredibly difficult mini-ship straight fly segments. After the last dual ball section, you'll transition to a single cube and hit the right orbs at the right time with right memory. After passing through several more difficult gameplay transitions, a final wave segment finishes this part off. This decoration is unique and excessively extreme for the shape decoration featured in this section.
 * 62-75% (Mactanow): This part starts out as very quick transitions at triple and quadruple speed between cube and wave. Next is a very short UFO section with a gravity switch, and transitions into very short segments of ship, wave, cube and one robot section. These short sections include many gravity switches, jump orbs, bouncers, and size changes. The rest of this part is similar to the beginning, with short segments and difficult timings. This part is finished off with one final straight fly section leading to a cube portal.
 * 76-83% (Djoxy + HequinoX): This section starts of with a cube in slow speed. The player has to jump in between multiple spikes, and this section has multiple timings. There is text above the player that says "Deco: Djoxy", and "Layout: HQ". Next is a short UFO segment with a jump orb. This transitions into a cube section where the player has to jump over many spikes and triple spike jumps. This transitions into double speed, and finally, a triple speed straight fly segment and a 5 spike jump to transition into iNighti's part.
 * 84-100% (iNighti): This part features special bright rainbow illuminations around the entire section, giving off a haze of the blocks and spikes throughout this part. After some straight fly and a large cube jump, there are excessive timings needed to pass through mini cube orbs, then pass through more straight fly sections, where the name is displayed underneath in the base of the blocks. After this, several spider jumps lead the way to extremely difficult UFO timings, with regular leaps and orbs alternating each jump. After another cube jump, a small cavern is shown for the last rocket part. Afterwards, the ending design of the level name is given, and the free coin. Beware, however, as staying on the ground will toggle a spike, and kill off all your hard progress!

User Coins

 * User Coin 1: At 30% at Metalface's part in the wave gamemode, if the player goes between two sawblades through a tight space, they will obtain the first coin.
 * User Coin 2: At 79%, if the player jumps and lands on a yellow jump pad, the player will bounce extra high to obtain the second coin.
 * User Coin 3: The final coin in the level. The player obtains it at the end by going through the heart at the end of the level, which is meant to be a reward for completing the level.

Trivia

 * This is one of the most stressful levels Sunix has beaten according to himself, surpassing Erebus, Yatagarasu, and even Sonic Wave.
 * Sunix verified Gamma on his account, but instead uploaded it onto MindCap's account using a verify hack due to him not wanting to go through the level again.
 * An official sequel is in progress at the moment, named Sigma.
 * Gamma once had a planned update in which it will turn to its unnerfed state and to be verified by Wooshi999. It was later cancelled and was replaced with an LDM and Coin Update, which was verified by Technical on June 17, 2018.