Phobos

Phobos is a 1.9/2.0 Extreme Demon mega-collaboration uploaded in 2.0 hosted by GMTSean and created by Tygrysek and other creators. The level was once considered as the second hardest demon level in Geometry Dash. However, this designation was disregarded due to its originally hacked verification, as the original level was near-impossible and was later nerfed. As the nerfed version is considered to be harder than Bloodbath, the original and unnerfed version of the level is likely more difficult than Sonic Wave and Yatagarasu.

On May 12, 2016, KrmaL (named Krazyman50 at the time) verified the level legitimately. The level has since been re-uploaded under his account where it regained its own demon rating. Surv beat it later on May 23, 2016, and Atomic beat it on August 18, 2016. Since then, multiple other players have beaten it, including SoulsTRK, Sunix, BlassCFB, and Skullo.

It is currently #45 on the Official Geometry Dash Demon List, above Sakupen Hell (#46) and below Carnage Mode (#44).

A remake of the unnerfed version of the level, Deimos, is being verified by npesta at the moment, with a current record of 56% as of November 17th, 2018.

Backstory
Phobos began as a mega-collaboration hosted by a former top 20 player named GMTSean. He had posted it in a Geometry Dash Facebook group back in April 2015 (note the group being original with more than 21,000 members).

GMTSean has given twenty places for players and creators; each were chosen based on their skills and abilities in the game and creating levels.

One of the first players to get involved was Tygrysek, then later was Andromeda. As soon as later on, many bigger names get involved in the mega-collaboration, including Smokes, Jo2000 and Skitten. However, contacting bigger names would be difficult; the level was built around 65% before WOOGI1411 was invited there.

In May 2015, the mega-collaboration, now named Phobos, was fully built. The team tried to contact Riot to verify; however, he declined the offer. After that, the team began to ask questions about who could verify this intense mega-collaboration. Some of the creators tried to verify it themselves. The furthest one was Riqirez, who reached 50% after nearly 30,000 attempts. However, one day later, Tygrysek informed the team that he had verified it. The level was then uploaded in November 2015 and got featured demon almost instantly.

However, hacking accusations started to arise, as rumors stated Tygrysek couldn't have possibly beaten such an extreme demon (at the time it was unnerfed) without footage in just a day. One of the first players to expose him was Loogiah, a popular Italian player and creator in-game. One day, he and Riot tipped off RobTop that Tygrysek hacked the level. This in turn caused Tygrysek to be threatened that the level would be unrated, unless it was verified legitimately.

On November 29th 2015, Tygrysek deleted the level's contents and made it a free demon. The description was changed to this:

"'I'm Sick of this thing. It was supposed to be a fun megacollab, it ended bad. Sorry for hacking this... RobTop please remove it.' "And the contents of the level was changed to a message which said this:"'Have fun. Sorry for hacking this... We (The Phobos Team) wanted it to be out as fast as Possible... And it ALL went wrong... Once again, sorry...'"However, a moment before the level was going to get unrated, he had a change of heart and returned to the level, this time with more visuals. The level remained demon rated. However, RobTop was later tipped off again, and the level got unrated and was deleted from the servers. This caused several rumors that one of the level's creators had a copy of the original level.

Since then, nobody ever tried this challenge, although there were several hacked copies floating around. WOOGI1411 once posted a video of the nerfed version, perhaps nerfed by himself (or maybe Tygrysek). The nerfed version was nerfed in 5 places (Sean, Palery, Kubson, Andromeda, and Riquirez), and WOOGI's popularity made many people look into it, and that caused even more players seeking the unnerfed version.

In early 2016, Krazyman50 took on the project of being the first to beat Phobos, using the nerfed version by WOOGI. He verified it after a few months of practice and 30,000 attempts. After Surv also beat it on stream, Robtop rated and featured it. It immediately rose to #2 on the demons list, just below Bloodbath (at that time).

Gameplay
0-4% (KoBaZz): The level starts off with a confusing but fairly simple mini cube part which requires crucial timing, filled with fake jump rings and gravity portals. This is probably the easiest part of the level.

4-8% (Tandrii) (a.k.a. Honeyb): The background and ground turns dark, and will enter a wave mode, which is moderately hard, Acropolis-like and requires crucial timing. The colored spikes in the Honeyb part will slightly change into black and white, then the cube mode which will last for a second will come and changes into a hard mini wave mode. The seemingly obvious route is blocked by a saw-blade and requires to go under, then you will see Honeyb's name.

8-13% (TechneT): Another cube part similar to those of KoBaZz's follows up but is slightly harder and needs more crucial timing. The design of his part is similar to those of Steam Chamber by Darnoc. It also resembles his own demon rated level, called Mechanic Megaforce.

13-19% (GMTSean): This is a very confusing UFO sequence with jump orbs. Here, the player requires very precise timing and jumps to pass. This part was one of few parts to be nerfed due to being near-on impossible.

19-26% (Jobet): This is a ship sequence in half speed with somewhat very tight spaces. This hard ship sequence has numerous gravity changes, a couple of mirror portals, speed and gravity portals that easily confuse inexperienced players. After this, Jobet's name will be seen.

26-33% (NiTro451) (formerly Eduard0): This is a wave segment that is extremely difficult due to tight spaces, saw-blades and double speed.

33-39% (iBlade): The player enters a mini ball sequence. Here, this part is tricky and requires more timing and jumps, especially switching gravity at the very end of platforms to avoid a spike on the other side. This is followed by a very tight wave segment with gravity portals. iBlade's name moves up letter by letter at the start of this wave segment, suggesting it was added during Update 2.0. In addition, iBlade's part also closely resembles WOOGI's part in The Ultimate Phase.

39-45% (Palery): This is a mini ship sequence with numerous speed changes, designed to easily throw the player off. A triple speed mini wave with invisible slopes follows, but that segment is actually rather simple in comparison to some parts of the level (originally, the first double-speed portal has a pink jump ring spike jump, but that nerfed because it was ridiculously hard).

45-49% (xSmokes) (TerraSmokes): The level's color suddenly changes into green. The player enters a mini ball segment. This part has an annoying amount of precise timing, and most of the level composes of fake lining and invisible platforms. Then comes a UFO segment with a purple background.

49-51% (Jo2000 ): The player enters a half speed ship sequence with jump rings, gravity portals and extremely tight spaces. Halfway through, the player goes mini and completes the ship (as seen in the picture above).

51-58% (DreamEater): This is a hard triple speed wave segment with a gravity switch halfway, then another straight fly segment with size changes and gravity portals everywhere. There is a brief wave section towards the end.

58-61% (Tygrysek): This is a triple speed dual ship sequence which briefly becomes half speed in the middle.

61-63% (Iqrar99): A short but really hard mini UFO/mini ball mixed dual, similar to that of Ditched Machine.

63-68% ('Skitten'): A normal speed ship sequence with clusters of saw-blades. The part has many gravity portals and yellow jump rings that are hard to time. The player suddenly changes to a UFO with numerous gravity portals and even more jump rings.

68-72% (Kubs0n): In the old version, this part starts off with a mini ship sequence, than changes to a mini wave leading through tight spaces, difficult timings and hard to notice objects. The mini wave game-play is actually slightly similar to a part from Sonic Wave. In the nerfed version, rather than being in the mini-wave, the player is a regular wave instead.

72-75% (Andromeda): It resembles the looks of Andromeda's collaboration Lunatic Doom Machine, that is filled with crosses, with an upside down half speed ship sequence with a one-block-wide straight fly. The ship was originally mini. However, it became a normal ship due to Kubs0n's part being nerfed with a normal ship/wave mode.

75-79% (Caernarvon725): Made after the release of Update 2.0, this ball sequence has many tight spaces, speed and size portals, and crucial timing. The name "Caernarvon" can be seen towards the end.

79-82% (Razur): His name appears, then the player is transported up to a short but hard UFO part with moving obstacles requiring somewhat difficult timings.

82-90% (WOOGI1411): The player will enter a ship sequence, then a short ball segment, then a second ship sequence. A rotating group of saw-blades, being rotated by a move trigger which needs to be dodged, if not, can be hit. This part requires a notorious amount of straight fly and is quite difficult. A robot part will be seen but it will only last for a second, then it returns to a brief triple speed cube segment. A "Take a Break" text will appear (originally, it says "You went too far nub, now DIE," and the background is gray in color as well as the text is not moving).

90-100% (Riqirez): The last part is a triple speed mini ship sequence, with a cluster of small invisible spikes and blocks, portals, jump pads, and jump rings can be seen, resembling NePtunE's demon level Doomsday II (albeit in ship mode). There are crosses made out of gradient decoration can be seen. Beforehand, it was a near-impossible non-sync mini ship/cube section but was made just a mini ship after the nerf.

The level will end as a hall of the people who participated in the mega-collaboration, with the sentence: "Congratulations! You have completed one of the hardest megacollabs in GD!" Underneath all the text ”Hacked by Tygrysek“ appears, which is then quickly replaced by ”Verified by Krazy”. It was originally “Verified by Tygrysek".

Trivia

 * This is considered to be one of the hardest levels ever to be created in Geometry Dash, because the level is extremely long and has annoying amounts of difficult timing and straight fly. Some consider it to be on par with or even harder than Bloodbath.
 * Phobos is the name of one of the satellites of Mars and is also the name of the Roman God of Horror.
 * The song "Phobos" has several voice lines in it. "Critical Error" can be heard at Jobet's part, "Step Forth and be recognized", can be heard at Dream Eater's part, "Who of you shall rise" can be heard at Iqrar99's part, and "Blood for the blood god" can be heard at Andromeda's part.
 * There is no Greek or Roman god representing "Blood."
 * To date, Surv, Atomic, Ozzy612, Krazyman50, SoulsTRK, BlassCFB, Sunix, and Skullo are the only players to beat the level legitimately.
 * Sunix currently has the least number of attempts in Phobos, with 3,478 attempts.
 * COSINE and DryBones were originally planned to be in the collaboration, but they never replied to requests.
 * Riqirez's part was originally a near-impossible dual segment (it used to be a mini ship/mini cube mixed dual), until Tygrysek re-verified the level and nerfed it to a mini ship sequence.
 * The original level was threatened to be unrated due to the fact that Tygrysek hacked it, so then he changed it into a free demon. It was then changed it back to its original version and then the level was unrated due to hacks by someone tipping off RobTop and then removed from the servers. However, it was re-uploaded by KrmaL.
 * There is an error at Jo2000's part; there is a missing block that was apparently deleted by accident (pictured above, as shown on the bottom right).
 * The parts that were nerfed are: GMTSean, GW Palery, Kubs0n, Andromeda, and Riqirez.
 * EndLevel may have completed Phobos off camera and has video evidence but it may be hacked.
 * GMTSean, one of the creators of Phobos, has also uploaded the unnerfed version of Phobos (there is a secret way at the end of Kobazz's part to allow Sean to easily verify the level). He still has not released the password to it, however.
 * During the verification progress of Phobos, Jobet put a secret way near his signature to allow verifying much easier, which caused a music bug. This bug was later then resolved.
 * EndLevel started a 2.1 mega-collaboration called Deimos, which is a buffed rebirth of Phobos.


 * Even though Conical Depression looked near-impossible and was claimed by KrmaL to be his possibly hardest beaten level in general, Phobos is still his second hardest level ever beaten, as the hardest level he has currently beaten is Black Blizzard.
 * Surv also claimed that this is the second hardest demon level he has ever beaten so far, leading some people to claim that the level is easier than Bloodbath.
 * Phobos is the son of Mars/Ares, which also has a similarity to Deimos, which is an upcoming sequel to Phobos and another son of Mars/Ares.
 * In Greek mythology, Phobos is the god of fear, while Deimos is the god of panic.
 * In real life, Phobos and Deimos are both moons of the planet Mars.