# u5d: a semantic-match Ultima V decompilation

> u5d reconstructs C source for Ultima V: Warriors of Destiny and compares it with the MS-DOS v1.16 program at the assembly-semantic level. The author reports that the modern version can be played through to the ending using original game data. The author reports approximately 95% matching for ULTIMA.EXE, excluding assembly functions, and approximately 95% for the overlays.

- 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/wonst719/u5d>
- Primary source: <https://github.com/wonst719/u5d/blob/6c7085e56fe9f033ac950c90901ca7927a4184e5/README.md>
- Catalog page: <https://awesomerea.org/resources/u5d-ultima-v-case/>
- Record JSON: <https://awesomerea.org/resources/u5d-ultima-v-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/u5d-ultima-v-case/index.md)

## Requirements & limits

- **Prerequisites:** Original Ultima V data files are required to play.
- **Prerequisites:** Windows builds use Visual Studio 2026. The DOS target uses DJGPP; the Microsoft C 5.1 target is used for disassembly matching and cannot currently link an executable.
- **Limits:** The original linker is unavailable, so a byte-identical binary match is not currently possible; bugs may remain.
- **License:** No licence file in the repository.

## Primary sources

1. <https://github.com/wonst719/u5d/blob/6c7085e56fe9f033ac950c90901ca7927a4184e5/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.