This wiki is meant to be a complete reverse engineered technical specification for the Phantasy Star Online games. Everyone is encouraged to correct errors and add new information.
Curious about the technical details of PSO, want to understand some source code you found online or want to create a new tool for PSO? Start here:
Architecture - High level overview of how PSO works.
Network Protocol - Network protocol details.
File Formats - Overview of the various file formats Sega used for PSO.
Backups of this wiki will be made daily and pushed to this public Git repository: https://github.com/jakeprobst/psodevwikibackup.