# OpenGromada: reconstructing the Sigma Games engine

> OpenGromada reconstructs the engine used by Sigma Games titles including AS1/ZS1, Theseus, Crazy Lunch and Locoland/Steamland. Its C++20 executable reads the user's game resources and supports multiple platforms and architectures, widescreen display and gamepads.

- Type: Case study
- Targets: Game
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-08
- Added to the catalog: 2026-11-08
- Original resource: <https://github.com/siohaza/OpenGromada>
- Primary source: <https://github.com/siohaza/OpenGromada/blob/9b1e839c2e220bde0765b100ee5dc06139603413/README.md>
- Catalog page: <https://awesomerea.org/resources/opengromada-case/>
- Record JSON: <https://awesomerea.org/resources/opengromada-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/opengromada-case/index.md)

## Requirements & limits

- **Prerequisites:** The relevant game's objects.res and data directories are required.
- **Prerequisites:** Building requires CMake or Premake, a C++20 compiler and SDL3; Steamworks SDK and FFmpeg 6+ are needed for the named optional features.
- **License:** Sustainable Use License 1.0.

## Primary sources

1. <https://github.com/siohaza/OpenGromada/blob/9b1e839c2e220bde0765b100ee5dc06139603413/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.