It will come as no surprise to fans of Red Dead Redemption 2 that Rockstar’s huge game world is full of hidden mysteries and Easter eggs. Some of them, however, require diving into the game’s files to fully uncover.

One Red Dead Redemption 2 fan has solved the mystery of the River Monster, which arose based on some strange files found in the game. What they discovered hints at some of the strangest content cut during the development of Rockstar’s epic western.

RELATED: 10 Open-World Games That Are Actually Longer Than Red Dead Redemption 2

The River Monster Audio Files

In the Red Dead Redemption 2 files, players can find an audio file belonging to an unknown creature in the game world. The file is named RIVERMONSTER, and the audio ranges from bizarre to downright eerie. Some of it sounds like roars mixed with a ship’s foghorn blaring, while some of it sounds like the growls of a big cat.

The foghorn sounds give some insight into what may have inspired the River Monster’s sound. Foghorns were also used to help create the sound of the Tripods in the 2005 War of the Worlds movie. The Tripod is a “fighting machine” used by the aliens. In Steven Spielberg’s adaptation, the aliens themselves also somewhat resemble the Tripods, though it is unlikely that this was the plan for the design of the River Monster in Red Dead.

Unfortunately, there is no way to tell for sure what the River Monster was actually supposed to look like in the game itself. Players can find a listing for a PED model in the game’s files, which reads A_C_RIVERMONSTER_01. However, the Red Dead 2 PED model was never created, suggesting that while the River Monster was originally planned, it was probably cut earlier in development. It’s even possible that the challenge of creating the monster itself led to the creature being taken out of the game. However, there are still a few hints players can find in the release version of Red Dead Redemption 2 which might lend some insight into what the River Monster’s PED model could have looked like.

RELATED: Red Dead Redemption 2's Madam Nazar Secret Stories Explained

The Design of Red Dead's River Monster

The original River Monster audio files help infer what the River Monster might have looked like. The files which sound like a big cat are shared with a lion in the game. The lion is found as part of the stranger mission “He’s British, Of Course – 4." In the mission, the player is told to track down a fake lion which actually turns out to be real.

The lion and the River Monster don’t just share their sound. The files for the River Monster reveal that the creature couldn’t be picked up or skinned, but it could be looted. The River Monster would have dropped crustacean meat, though there’s nothing else to indicate that it would have been related to crabs. The Red Dead lion also cannot be picked up or skinned but can be looted, dropping it's paw as a trophy that the player character can take. This makes it seem likely that the River Monster would have also been a unique NPC used for one specific quest.

There’s also another missing NPC which was likely going to be included in this quest, but was cut from the game. The game files show that a camel was planned to exist in Red Dead Redemption 2, and it’s likely that it would have been a part of the same stranger mission. In the retail release, “He’s British, Of Course” starts when the player finds a broken-down circus caravan in Lemoyne. The missions had the player character tracking down a zebra, a tiger, and a lion.

The camel doesn’t exist in the game, but it is still included as one of Red Dead Redemption 2’s cigarette cards. If a similar decision was made for the River Monster, cigarette cards in the game give some insight into some of its possible designs.

There are three boat cigarette cards which have sea monsters in them in Red Dead Redemption 2. One is the Schooner Card, which shows a ship with a large tentacle coming out of the water behind it, probably a reference to the mythical Kraken of maritime mythology. The Balener Whaling Vessel card shows a huge whale, though that would have made a very different sound to the audio files. The US Frigate card shows a shape in the distance clearly designed after the Loch Ness Monster, which – judging by the fact that it’s the only creature shown that supposedly lives in fresh water – is probably the most likely candidate for the River Monster’s design.

The fact that the River Monster shared the same qualities as the lion in the stranger mission probably means that the creature would have been a part of a different stranger mission which was cut from the game. Between robotic armies and implied time travel in Red Dead 2, the stranger missions tend to have the most outlandish inclusions in the game, so a Loch Ness Monster-inspired cryptic wouldn’t be out of the question, though it also could have been cut for seeming to unambiguously fantastical.

Fans will continue to search the Red Dead Redemption 2 files in search of more mysteries and their solutions. Rockstar’s game world is huge, but that’s just the tip of the iceberg, and there are many more secrets to be found that hint at cut content and abandoned ambitions for the game. With so many rivers in the Red Dead Redemption 2 map, however, it’s very difficult to determine where the River Monster might have been planned for, or to infer who might have been involved in the stranger mission based on its location. For now, however, keen-eyed Red Dead fans can only speculate as to what might have been planned for the creature, and how it might have fit into a RDR2 stranger mission.

Red Dead Redemption 2 is available now on PC, PS4, Stadia, and Xbox One.

MORE: Comparing Red Dead Redemption 2 Screenshots to Real-World Locations