Bloodborne’s “Tomb Prospectors” have spent years navigating the game’s enigmatic dungeons, hoping to find something new. They’ve conquered and categorized hundreds of dungeons, with every creature, trap, and territory seemingly known and accounted for. They’ve played Bloodborne enough that the player-led group might know the hardcore action game better than the creators, From Software. And the club says they’ve found a huge Bloodborne glitch that prevents fans from seeing everything the game has to offer.

Bloodborne lets players create “Chalice Dungeons,” which contain randomly generated areas full of unpredictable threats. As Chalice Dungeons can be shared online with other people through specialized codes, Prospectors often explore areas together with the aim of finding new dungeon configurations. Their adventurous pursuit is serious enough that the Prospectors even have a uniform that denotes membership to the group. Years later, after much of the world has moved on and From Software is making new games, the Prospectors still go spelunking within Bloodborne with surprising regularity.

With this in mind, one year ago, GameFaqs user kazin1979 posted a thread detailing a surprising discovery: no matter how many of the higher difficulty Isz-type Chalice Dungeons they generated, the game kept spitting out a small number of variations. Hundreds upon hundreds of Isz dungeons were assembled for study, and yet only 32 types of areas popped up. Compared to the hundreds of variants that other Chalice Dungeons offered, something seemed wrong with the way Bloodborne was generating new Isz areas.

“In 11 hours of creating [Isz Chalice Dungeons] today I saw the exact same dungeons repeating over and over,” kazin1979 wrote. “Same layout, same bonus area layouts. Same enemy positions, same loot, same coffin / chest loot, and same boss. Same layer two also when I went down and checked. The exact same dungeon pulled from the pool.”

And so, the Bloodborne aficionados dug into the game’s files to see if something was out of place. This is where Prospector Zullie discovered that, while From Software marketed Chalice Dungeons as completely random, they aren’t actually coded that way. Prospectors claim that Bloodborne has a set number of Chalice dungeons with specific layouts that it can pull from, and the game only selects these predetermined dungeons at random. To casual players, Bloodborne’s repertoire of dungeons is large enough that it might as well be infinite. With Isz, however, dedicated players were bumping into the seams holding Bloodborne together.

The Tomb Prospectors got to work and started mapping Isz dungeons layouts, including enemy and loot positions. The team even developed a special system that allowed them to identify a dungeon just through a handful of screenshots without actually having to explore the space generated by the game, all in the name of finding out what they were doing wrong. Why couldn’t they see everything Isz had to offer? What was wrong with the game?

The team tried experimenting with how they created Chalice Dungeons in the hopes of discovering what exactly was preventing them from seeing the larger Isz pool. The more dungeons they generated, the more theories abounded. Maybe it had to do with the character level or how many dungeons players had visited before? But no matter what they did, the group kept falling into the same dungeons over and over again.

Eventually, the team got a hunch that maybe collecting too much loot within an Isz-type dungeon would lock them into the glitch. So, Prospector member DrAnger90 decided to make a fresh character before diving in into Isz-type dungeons. It worked. After months of mapping out the same Isz dungeons over and over again, the team finally saw something new. Eureka! The Prospectors immediately started to research their new playground.

Prospector MorosNyx and XTrin continued to make new dungeons, eventually crafting one that had a holy grail of a discovery: a wandering boss-type enemy in Isz, the dual-wielding Pthumerian Descendant. Nobody had ever seen something like that before in Isz, partially because of the glitch, but also because bosses are usually programmed to stay within a contained area.

It took six months of dungeon generation to get here, which might explain why footage of the boss has amassed nearly 400,000 views on YouTube. Hilariously, the team makes the Descendant follow them through the dungeon, eventually leading it to another mini-boss. The AI immediately starts fighting against each other, and it’s a spectacle to watch. “Exploring uncharted territory is thrilling, and any undocumented discovery turns into a strong shared emotion between us all,” said Tomb Prospector Altair Naruhodo.

The team isn’t done. If anything, breaking free of the Isz glitch has opened up a wealth of new opportunities to see things that other players have never encountered. Already, Altair says the team is discovering new sights within Isz despite already dedicating hundreds upon hundreds of hours to the game.

“Three years have passed since the release of the game, but we are positive the chalice dungeons still hold many secrets,” Altair says. “We carry on with our mission, searching for anything that, in the Bloodborne fashion, we can call the Unseen.”