In what is being called one of the most significant leaks in the gaming industry, over 70 games—some not yet announced—have had their Steam achievement lists leaked online. The leak includes games set to launch this year, as well as titles scheduled for release as late as 2027 and even games that have not been officially revealed. Steam, a digital distribution platform run by Valve, allows players to track achievements they earn in games, and these details are often tied closely to the game's storyline and mechanics. The leak has raised concerns for players and developers alike, particularly for story-driven games like Kingdom Hearts 4 and Persona 6. The achievement list for Kingdom Hearts 4 includes references to multiple unconfirmed Disney worlds, such as one based on Coco, which had not previously been confirmed. While Persona 6’s achievements are more cryptic, they may still provide clues about the game’s narrative. The inclusion of Persona 6 in the leak is notable because the game had no official release date, but its appearance on Steam suggests it may launch in 2027, following the release of Persona 4 Revival in early 2026. Among the other games mentioned in the leak are Fable, Gears of War: E-Day, and Silent Hill: Townfall. The leak also includes Judas, a game that had no official release date and was widely believed to have been canceled. Additionally, it reveals the existence of several unannounced titles, including a potential re-release of Professor Layton vs. Phoenix Wright: Ace Attorney, originally released on the Nintendo 3DS. The achievement lists were shared via Exophase, a website that helps users track their achievements across multiple gaming platforms. The method by which the achievements were uploaded to the site remains unclear. The leak has caused significant concern for Valve, the company behind Steam, as it could lead to serious repercussions with publishers, especially Japanese developers like Sega and Square Enix, who are likely upset about the leaks of Persona and Kingdom Hearts titles. Valve may be relieved that GTA 6 is not launching on PC, as the leak of its achievements could have caused even more controversy. As of now, Valve has not commented on the situation, though it is expected to provide a more detailed explanation than Nvidia did when it accidentally leaked a list of unannounced games in 2021.