In Grand Theft Auto 5, one landmark was visible practically no matter where you were in San Andreas: Mount Chiliad. “Claimed by the Spanish in 1769, Mount Chiliad is the highest peak in San Andreas, sitting at a height of 2,744 meters,” reads a sign at the nearby Silent Probe Mountain art installation. “Taken under Mexican control in 1821, it was then, and remains in American hands since 1847.”
It’s more than just a mountain, though. Once the player has achieved 100% story completion, standing atop the mountain at 3 a.m. during cloudy weather reveals a UFO, hovering in the night sky. It’s marked with an F.I.B. logo, aka the Federal Investigation Bureau, implying that it was created by the government. However, there’s also reason to believe that the mysterious aircraft is a hoax, because it doesn’t react to bullets, and raindrops nearby become pixelated.
The running theory is that it’s a hologram, as opposed to the two other functional UFOs in the game, which are physical objects. They’re located high in the sky above both Fort Zancudo and the Silent Probe Mountain respectively, they can both be collided with, and they emit electromagnetic pulses that cause the player’s vehicle to shut down if they get too close. There’s reason to believe they’re both also government-controlled: the former visually looks somewhat similar to a real-life B-2 Spirit stealth bomber and, when viewed using third-party software, has two human pilots inside. The latter also has F.I.B. printed on the side, much like the UFO above Mt. Chiliad.
Players knew there was at least one secret at the top of the mountain, thanks to graffiti on the back of the observation deck that reads “come back when your story is complete.” GTA Online revealed that the mountain is also home to a nuclear launch facility. But some players are convinced that Mt. Chiliad holds one final mystery that is still unsolved to this day.
Inside the tramway station near the summit, a mural depicts an abstract interpretation of the mountain itself. At the top is an eye, while the exterior of the mountain has lightning bolts emanating from it. Inside the mountain is a maze of perpendicular connecting lines. Each one connects to one of eight squares. Five of them are small, marked with an X inside. The three larger ones at the bottom of the picture show, from left to right, a UFO, a cracked egg, and a person wearing a jetpack.
One week after GTA 5 was released, on Sept. 24, 2013, fans created the Chiliad Mystery subreddit. For the last 13 years, users there have been dedicated to uncovering the secrets believed to be held within. The community worked out that the X’s correspond to petroglyphs hidden around the mountain, each of which depicts a weather status required for the Mt. Chiliad UFO to appear. There’s also a theory that each X also represents the roman numeral for 10, and since there are five of them, it’s representative of the 50 collectible spaceship (aka UFO) parts scattered across San Andreas.
In the GTA Online mission involving the nuclear facility, the player escapes by using a jetpack. Is that what the jetpack drawing on the mural is referring to? It’s one of the mural’s lingering riddles. It’s certainly plausible, if a little underwhelming, because the common belief was that unraveling the mystery would result in a permanent jetpack vehicle, usable in GTA 5’s single-player mode, not exclusive to Online. However, some think the jetpack just refers to the UFO above Fort Zancudo, because in GTA: San Andreas, the jetpack is found at the military base.
Then there’s the cracked egg. This has been the biggest source of confusion for the sleuths working on the mystery, and there are a number of theories. It could refer to the Epsilon cult, as they believe the world hatched from an egg. It could also tie in to the fountain by the Maze Bank Tower in Los Santos, as the two bear a close resemblance. Or there’s the most common theory, which is that it is simply a hint to the underwater UFO found in Paleto Bay, on the northern coast of San Andreas.
So with all of that in mind, there’s every chance that the mural is simply one giant hint to finding each of the UFOs in GTA 5. But believing that would also mean believing that the Chiliad mystery is solved, and there’s no fun in that, because it would be a seriously disappointing outcome. And for the users on the subreddit, that isn’t even a possibility.
There are hundreds of loose ends and theories players have discovered. Even in the last year, they’ve posted dozens of new ideas. Here’s user Alexisuwuu23, who is convinced an in-game film, “Capolavoro,” holds the secret because a billboard ad for it can be found at the location where streetlights form a question mark if looked at from the observatory, and it all ties into a disappearing ladder. “Intentional, obviously,” reads one reply. “Gotta be a marker or something. The hunt continues.”
In September, AntelopeIcy6558 posed a theory about the eight lights on top of the Maze Bank Tower helipad. “I believe that to solve the secret, you need to shoot these eight lights in a certain order,” the post reads. “Why? I believe there are eight locations around Los Santos that we need to find. Each of these locations from some angle resembles a keyhole, which is one of the main symbols of this mystery.”
There are other theories that think the mystery stretches beyond GTA 5, and also includes Red Dead Redemption 2. Cancelled DLCs and datamined files have revealed a vast array of potential clues, but since those projects were never officially released, they’re unlikely to ever provide a definitive answer. Then there are those who predict GTA 6 will provide a resolution.
Twelve years ago, user talkol made a post titled “pretty solid proof that the game was released without a jetpack or flyable UFO,” which outlined what is still the most damning evidence we’ve had: there is nothing hinting at either of those vehicles in the game’s files. Of course, that didn’t dissuade the masses, because posts like these have been non-stop for the last 13 years.
Last year, as reported on by IGN, YouTuber Gator Keys uploaded a video titled “This is The End of the Mount Chiliad Mystery.” He kicks it off by stating what many realists would agree with: “I’m not claiming I’m the first person to come to this conclusion. I’m sure many other players did in 2013, but for some reason, the Mt. Chiliad mystery remains in 2025. So there needs to be a video that puts an end to it before GTA 6 releases.”
Gator Keys goes into plenty of detail in the eight-minute-long video, but to sum it up, his explanation is that the mystery is nowhere near as deep as the community had believed. The answer is essentially that the government is all-seeing and all-powerful, as represented by the F.I.B. logos on the UFOs and the eye on top of the mural. It’s simply a satirical take on real life, similar to the idea of the Illuminati.
Ultimately, the “true” answer for the Chiliad mystery is irrelevant. The mystery itself spawned a thousands-strong community, with everyone cooperating and theorizing. It’s reminiscent of when that kid at school promised they’d found Mew underneath a truck in Pokémon Red and Blue. Easter eggs and gaming mysteries these days are usually solved within days, thanks to datamining and the sharing of information via the internet. GTA 5, on the other hand, whether intentionally or not, gave players something to talk about for 13 years.
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There’s no doubt GTA 6 will spawn plenty more theories and Easter eggs, whether they’re a continuation of the Chiliad mystery or something entirely new. It’ll also likely be the biggest video game of all time, whether it includes a decade-long mystery or not. But the longevity of the Chiliad mystery makes one thing clear: Rockstar is the champion of this type of lore, and including something similar, where the game never truly feels complete without it being solved, will keep a huge portion of the community occupied for years to come.







