Steam API Leak Exposes Dozens of Unreleased Games Including Avengers, Dune and Sonic
A Steam API issue appears to have exposed achievement data belonging to dozens of games that were not supposed to be publicly accessible, revealing both previously announced releases and a significant group of completely unannounced projects connected to franchises including Avengers, Dune, Sonic, Sea of Thieves, Stellaris and Twin Peaks.
Third party achievement trackers Exophase and SteamDB began detecting achievement information associated with unreleased Steam applications, including entries that did not yet have public game names. Exophase owner Mike Bendel explained that games with achievements that should have remained private had apparently become accessible through Steam's API, allowing automated tracking services to scan the information. The available evidence therefore points toward an API access or configuration issue rather than a conventional data breach.
The scale of the leak requires an important distinction. The current Steam API achievement leak report contains 85 list entries, but these are not 85 previously unannounced games. The list combines games that have already been announced but remain unreleased with projects that had not previously been revealed. Of those 85 entries, 18 are explicitly identified as unannounced, and one of those entries represents 2 separate unannounced Warhammer games. This means the current list contains at least 19 explicitly unannounced projects, although additional unnamed or unclear entries could also represent games that have not yet received formal announcements.
MORE STEAM ACHIEVEMENT LEAKS
— Forward (@ForwardLeaks) September 9, 2026
- Unknown Tetris Game
- The Avengers Game by THQ (prev cancelled, now being worked on again)
- Planet Zoo 2
- Game of Thrones: War for Westeros
- Gears of War: E-Day
- Beer Collecting Simulator
- Sea of Thieves
- Tropico 7
- Gundam Rouge Orbit
-… pic.twitter.com/FDKtpEC0Q3
Several already known games also appear in the data, including Dragon Ball Xenoverse 3, Final Fantasy Resonance, Persona 6, Persona 4 Revival, Kingdom Hearts IV, Gears of War E Day, Control Resonant and Gundam Rogue Orbit. Their presence does not constitute a new game announcement, but achievement information can still expose gameplay progression, locations, characters, bosses and other details that publishers may not have intended to reveal.
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2 unannounced Warhammer games
4loop
ACE COMBAT 8
ALF game
Attack on Titan 3
Brazilian Drug Dealer 4
Clive Barker’s Hellraiser
Clutch
Control Resonant
Crazy Taxi: World Tour
Custom Hobo
Danganronpa 2X2
Deus Ex Remaster
Disney Pixar Toy Story: Retro Roundup! + Toy Story 3 Complete Edition
DRAGON BALL XENOVERSE 3
Dragon Quest Monsters: The Withered World
Dynasty Warriors 3 Complete Remastered
Fate Extra Record
FINAL FANTASY RESONANCE
Fright Train
Gears of War E Day
Grave Seasons
Gundam Rogue Orbit
HoloTrials
Horizon Hunters Gathering
Judas
Kena: Scars of Kosmora
Kingdom Hearts IV
Last Epoch
Lords of the Fallen II
Mega Man Dual Override
Metal Max 2 Reload
Metro 2039
Minecraft Dungeons 2
Nivalis Nights
Order of the Sink Star
Penis Bird
Persona 4 Revival
Persona 6
PGA Tour 2K27
Professor Layton and the New World of Steam
PUBG DED.NET
Rayman Origins
Remothered: Red Nun's Legacy
Restitched
Rhapsody in Scarlet
Road Kings
Silent Hill: Townfall
Squadron 42
Star Trek Outposts
Star Wars Galactic Racers
Stranger Than Heaven
Stupid Never Dies
Tales of Eternia Remastered
Terranigma
Thief: The Dark Project
Tomb Raider: Legacy of Atlantis
Touhou Kyoumakou
Trails in the Sky 2nd Chapter
Trine 6: Together in Time
Tropico 7
Turok Origins
Unannounced Avengers game
Unannounced Balatro sequel or spin off
Unannounced Brawl Stars game
Unannounced Candy Crush title
Unannounced Dune game
Unannounced Heroes of Newerth project
Unannounced Nickelodeon life simulation game
Unannounced Raiden Fighters Collection
Unannounced Sea of Thieves sequel or 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
Uta Macross
Valor Mortis
Wardogs
Warhammer Survivors
Warrior Cats: Clans of the Forest
Witchbrook
The list should still be treated cautiously. Achievement records can belong to active projects, internal builds, prototypes or games whose names and scope may change before public announcement. Their appearance through Steam infrastructure is strong evidence that corresponding applications and achievement data exist, but it does not guarantee that every unannounced project will eventually receive a commercial release.
The biggest story is not that more than 50 completely secret games suddenly leaked. That interpretation exaggerates what the data actually shows. The exposure covers a much broader collection of unreleased software, including many games that players already know about, alongside at least 19 projects that are explicitly identified as unannounced in the current list.
Those unannounced entries are still significant. Avengers, Dune, Sonic, Sea of Thieves, Stellaris and Twin Peaks alone represent major franchises whose future projects could have been revealed considerably earlier than their publishers intended. The incident also highlights how much information modern game distribution infrastructure can expose before marketing campaigns begin. A trailer may remain locked inside a publisher, but App IDs, achievement databases and backend configuration can become equally valuable sources of information when something goes wrong.
Which of the unannounced projects interests you most: Avengers, Dune, Sonic, Sea of Thieves, Stellaris, Twin Peaks or one of the other games exposed through the Steam API?
