# OpenMU: a reconstructed MU Online server and packet reference

> OpenMU reconstructs a MU Online server from scratch, focusing on the Season 6 Episode 3 English client protocol. Its C# implementation is accompanied by packet references that map identifiers, byte fields, send conditions and effects on the game client.

- Type: Case study
- Targets: Game · Protocol
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-06
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/MUnique/OpenMU>
- Primary source: <https://github.com/MUnique/OpenMU/blob/b03564abe601b8560eba40693c11953be46dd16d/README.md>
- Catalog page: <https://awesomerea.org/resources/openmu-case/>
- Record JSON: <https://awesomerea.org/resources/openmu-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/openmu-case/index.md)

## Requirements & limits

- **Prerequisites:** A compatible MU Online client is needed to connect to the server.
- **Limits:** The project focuses on Season 6 Episode 3 using the English protocol and remains under development.
- **License:** MIT licence.

## Primary sources

1. <https://github.com/MUnique/OpenMU/blob/b03564abe601b8560eba40693c11953be46dd16d/README.md>
2. <https://github.com/MUnique/OpenMU/blob/b03564abe601b8560eba40693c11953be46dd16d/docs/Packets/C1-07-MagicEffectStatus_by-server.md>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.