# RO3Emu: reconstructing a Ragnarok Online 3 server

> RO3Emu reconstructs a server for the Ragnarok Online 3: Genesis game client. Its C# and .NET 10 code implements multiplayer systems and client-facing message routes, while research notes document observed client behavior and mark uncertain behavior as guesses. The launcher can find an existing game installation or download the game from its update servers.

- Type: Case study
- Targets: Game · Protocol
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-07
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/aethai/ro3emu-server>
- Primary source: <https://github.com/aethai/ro3emu-server/blob/4559db162df0ef0739ca58690e5a64164ccf4fb9/README.md>
- Catalog page: <https://awesomerea.org/resources/ro3emu-server-case/>
- Record JSON: <https://awesomerea.org/resources/ro3emu-server-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/ro3emu-server-case/index.md)

## Requirements & limits

- **Prerequisites:** Ragnarok Online 3: Genesis game files, from an existing installation or through the launcher's download option.
- **Prerequisites:** The .NET 10 SDK to run from source.
- **Limits:** Some server behavior remains a documented guess.
- **License:** GPL-3.0 license.

## Primary sources

1. <https://github.com/aethai/ro3emu-server/blob/4559db162df0ef0739ca58690e5a64164ccf4fb9/README.md>
2. <https://github.com/aethai/ro3emu-server/blob/4559db162df0ef0739ca58690e5a64164ccf4fb9/docs/README.md>
3. <https://github.com/aethai/ro3emu-server/blob/4559db162df0ef0739ca58690e5a64164ccf4fb9/docs/systems/skill-protocol.md>

## More in Games

- [RS Mod: RuneScape server-mechanics reconstruction](https://awesomerea.org/resources/rsmod-runescape-case/index.md) · Case study
- [rsc-server: reconstructing a RuneScape Classic server](https://awesomerea.org/resources/rsc-server-runescape-classic-case/index.md) · Case study
- [Rush 2 Recompiled: native PC build of Rush 2: Extreme Racing USA](https://awesomerea.org/resources/rush2-recompiled-case/index.md) · Case study
- [rustify-doom: reconstructing Doom in Rust from a stripped binary](https://awesomerea.org/resources/rustify-doom-case/index.md) · Case study
- [samp-client-re: a partial SA-MP client reconstruction](https://awesomerea.org/resources/samp-client-rea-partial-reconstruction-case/index.md) · Case study
- [Sapphire: a reconstructed FINAL FANTASY XIV 3.3 server](https://awesomerea.org/resources/sapphire-ffxiv-server-case/index.md) · Case study

## 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.