You download the 556 songs, and they are yours forever. No subscription. No battle pass. No "seasonal rotation" removing your favorite track. It sits on your hard drive, playable even if the internet goes out.
To the uninitiated, O2Mania is a standalone, open-source rhythm game simulator designed specifically to read .OJM (audio files) and .OJN (note chart files) from the original O2Jam. But to veterans, it is the savior of O2Jam.
When the official game shut down in many regions, players lost access to hundreds of songs they had purchased or earned. O2Mania bypassed the need for a central server, allowing players to take their existing song libraries and play them offline, with zero latency and zero subscription fees.
The version we are highlighting—labelled as containing All 556 Songs—is the definitive "complete pack." It represents the peak of O2Jam’s official release, covering every genre from Trance and Techno to Rock, Pop, and Classical remixes.
O2Mania is a standalone, offline rhythm game replicating and expanding O2Jam gameplay, bundling all 556 songs from the original library with modern quality-of-life features, improved input handling, and offline matchmaking/leaderboards. O2Mania -Offline O2Jam - All 556 Songs Included- Game
Authentic Gameplay Modes
Difficulty & Charting
Controls & Input
Audio & Visual
Performance & Compatibility
Scoring & Leaderboards
Customization & Mods
Progression & Achievements
Song Management
Accessibility
Safety & Offline Focus