A massive Steam leak appears to have exposed achievement lists for dozens of upcoming and previously unannounced games, potentially revealing everything from Persona 6 to remasters of Deus Ex and Thief.
The leak surfaced on September 9 through achievement-tracking site Exophase after data that should seemingly have remained private became accessible through Steam‘s API.
More importantly, some of the leaked achievement lists contain secret achievements and potential story spoilers for games that haven’t even been released.
Steam Leak Includes Persona 6, Fable, Kingdom Hearts 4 and More
The exposed data reportedly includes achievements for numerous major upcoming games alongside projects that haven’t previously been announced.
Some of the most notable titles include:
- Persona 6
- Kingdom Hearts 4
- Basna
- Gears of War: E-Day
- Tomb Raider: Legacy of Atlantis
- Kontrola: Rezonantno
- Okupljanje lovaca na horizonte
- Judas
- Silent Hill: Townfall
- Stranger Than Heaven
- Kena: Scars of Kosmora
- Minecraft Dungeons 2
- Deus Ex Remastered
- Thief: The Dark Project Remastered
- Attack on Titan 3
- 4:LOOP
- Valor Mortis
- Road Kings
- Stuntman: Hollywood
- WARDOGS
Several dozen additional projects were reportedly exposed, including potential games connected to The Walking Dead, Shrek, Twin Peaks and Dune.
Some entries currently appear only under Steam AppIDs, making their identities less certain.
Private Steam Achievements May Have Become Publicly Accessible
According to Exophase’s owner, the unusual influx appears to have occurred because achievement information normally kept private suddenly became accessible through Steam’s API.
“Seems like a possible screw up on Valve’s end, a bunch of games with achievements that should be private are accessible through the API right now.”
The leak could be particularly damaging because achievement names and descriptions often reveal bosses, locations, characters and major story events long before players encounter them.
It has already produced potentially significant information about Kingdom Hearts 4, while entirely unannounced projects may have been exposed before their publishers intended to reveal them.
Until the companies involved officially announce these games, however, titles uncovered solely through the leak should still be treated cautiously. If the exposed Steam data is legitimate, this could be one of the biggest gaming leaks of 2026.
Update*
- Unannounced Avengers game
- Unannounced Balatro sequel/spinoff game
- Unannounced Brawl Stars game
- Unannounced Candy Crush title
- Unannounced Dune game
- Unannounced Heroes of Newerth
- Unannounced Nickelodeon life-sim Animal Crossing-esque game
- Unannounced Raiden Fighters Collection
- Unannounced Sea of Thieves sequel/spin-off
- Unannounced Shrek 2 Remaster or Shrek-related game
- Unannounced Sin Reloaded
- Unannounced Slime Rancher game
- Unannounced Sonic game
- Unannounced Stellaris game
- Unannounced Toem 2
- Unannounced Twin Peaks game
- Unannounced Walking Dead Collection
