# ClassicUO: Ultima Online Classic Client reimplementation

> ClassicUO recreates the Ultima Online Classic Client in C# on FNA-XNA. Its source includes game asset loaders and client logic for a separately obtained installation, and the authors describe testing primarily against free shards.

- Type: Case study
- Targets: Game
- 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/ClassicUO/ClassicUO>
- Primary source: <https://github.com/ClassicUO/ClassicUO/blob/ee79d7ebc1cc0e53ff84fe6cae17d389e2737f93/README.md>
- Catalog page: <https://awesomerea.org/resources/classicuo-case/>
- Record JSON: <https://awesomerea.org/resources/classicuo-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/classicuo-case/index.md)

## Requirements & limits

- **Prerequisites:** Requires a legally obtained copy of the Ultima Online Classic Client.
- **Limits:** The client is under heavy development and is primarily tested against free shards.
- **License:** LICENSE.md states BSD-2-Clause, while README.md states BSD 4.

## Primary sources

1. <https://github.com/ClassicUO/ClassicUO/blob/ee79d7ebc1cc0e53ff84fe6cae17d389e2737f93/README.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.