Massive Steam Leak: Persona 6, Kingdom Hearts 4, and Ace Combat 8 Exposed by Achievements
The video game industry woke up to absolute chaos this Wednesday, September 9, 2026. A major technical glitch in Steam's backend API accidentally exposed internal achievement lists for dozens of unreleased games.
The leak was immediately caught and tracked by stat platforms like Exophase and eagle-eyed users on r/GamingLeaksAndRumours, quickly revealing the unprecedented scale of this publisher nightmare.
An API Breach on Par With Gaming's Biggest Leaks
In terms of sheer scope, the incident instantly calls to mind the infamous 2021 GeForce NOW leak. Only this time, these are not vague internal codenames: they are fully detailed Steam achievement lists, complete with titles, descriptions, and exact unlock conditions.
For the publishers involved, the fallout is severe: major story spoilers, named locations, and core gameplay mechanics are now circulating openly across the internet.
Persona 6 and Kingdom Hearts 4 Headline the Fallout
The crown jewel of the leak is without a doubt Persona 6. The unlocked achievements reveal that the upcoming JRPG is set in the port city of Yokohama and centers around a mysterious organization dubbed "Hex."
Even more surprising for longtime Atlus fans, the iconic Social Link system appears to have been rebranded as "Connections," while several major dungeons are already named in the leaked metadata.
Over at Square Enix, Kingdom Hearts IV took a massive hit as well, with multiple explorable worlds and story progression achievements for Sora out in the wild. For PC gamers still waiting on PC versions of major blockbusters, their presence in Steam's backend database confirms at least one vital piece of good news: both titans are slated for day-one or near-simultaneous launches on PC.
Ace Combat 8, Dragon Ball, and Retro Surprises
Bandai Namco was also hit hard by the breach. The next chapter in its flagship flight combat franchise showed up under the official title Ace Combat 8: Wings of Theve, with achievements confirming four classic playable Namco arcade titles integrated into the package.
The database also unearthed trophies for Dragon Ball Xenoverse 3, a full remake titled Persona 4 Revival, Remedy's Control: Resonant, and an unexpected PC port of Metal Max 2 Reloaded.
| Game | Publisher / Studio | Details Confirmed by the Leak |
|---|---|---|
| Persona 6 | Atlus / SEGA | Yokohama setting, "Hex" faction, "Connections" mechanic |
| Kingdom Hearts IV | Square Enix | Explorable worlds and Sora narrative progression achievements |
| Ace Combat 8 | Bandai Namco | Official subtitle "Wings of Theve" and bonus retro Namco titles |
| Dragon Ball Xenoverse 3 | Bandai Namco | New story arcs and power level milestones |
| Metal Max 2 Reloaded | Success / Kadokawa | Full Steam PC port with complete achievements |
What This Means for PC Gaming and the Community
While Valve moved quickly to plug the API security hole early this morning, the leaked data had already been scraped and mirrored by thousands of users worldwide. The coming weeks will be a minefield across social media for any fans hoping to go into these games spoiler-free.
With the video game release calendar already packed to the brim this fall, this historic leak is forcing publishers to scramble. The marketing roadmaps for Japan's biggest gaming giants just went up in smoke.
