Open-source alternatives to OpenRA

Space Station 14 is a C# multiplayer game and roleplay simulation framework. It is built upon an Entity-Component-System (ECS) game engine that separates logic into systems and data into components to manage complex entity interactions. The project functions as a grid-based physics simulator with a YAML data-driven prototype system for defining game objects. The project features a specialized 2D sprite rendering engine that maps server-side appearance data to client-side shaders. It implements a networking model with client-side prediction and dirty-flagged state synchronization to reduce inp

OpenTTD is an open-source game engine and transport simulation game. It provides an isometric sandbox environment for building and managing complex logistics and transport networks. The project functions as a multiplayer simulation sandbox where users can build infrastructure cooperatively or competitively in a shared virtual world. The platform is designed as a moddable simulation system that supports external assets, graphics, and gameplay modifications. It includes mechanisms for downloading and integrating add-on content and utilizes a plugin-based system to extend game mechanics beyond t

CorsixTH is an open-source game clone and hospital management simulation game. It functions as a reproduction of a classic management title where players coordinate staff and treat patients to manage a medical facility. The project includes a level editor tool for designing original maps and campaigns. It also features a customizable input system that allows users to map game hotkeys and personalize control schemes. The simulation supports game localization to translate interface text and dialogue into multiple languages.

Importer and scripts for Warcraft II: Tides of Darkness, the expansion Beyond the Dark Portal, and Aleonas Tales

Beyond-All-Reason is a real-time strategy game and 3D military simulation focused on large-scale tactical combat, base building, and resource management. It functions as a competitive multiplayer platform featuring ranked lobbies and skill-based matchmaking. The project includes a custom map editor for designing unique game levels and environments through structural and thematic configuration. The simulation covers military-industrial economy management, including resource extraction and asset recovery. Tactical gameplay involves commanding army formations, using radar for enemy unit detecti

This repository contains the original source code for a classic real-time strategy game, serving as a legacy game engine implementation for managing units, maps, and combat mechanics in a military strategy setting. It functions as a real-time strategy game source code archive intended for preservation and technical study. The codebase acts as a game modification base, allowing developers to create custom content and modifications using the original source. It provides a foundation for retro game modding and software archeology to analyze how historical game mechanics were programmed. The pro

Spring is a cross-platform game engine and framework designed specifically for the development and execution of multiplayer real-time strategy games. It provides a high-performance simulation environment for managing large-scale battles and unit movements across different operating systems using a shared codebase. The engine functions as a multiplayer game server and networking layer, coordinating real-time game state and match synchronization between remote players. It includes a dedicated lobby client system for multiplayer match coordination as well as the capability to execute single-play

Defold is a cross-platform game engine and integrated development environment used to create 2D and 3D games for desktop, mobile, and web targets. It combines a game development IDE for asset and scene management with a multi-platform build system and a scripting environment based on Lua. The engine includes a specialized headless runtime for hosting game servers and performing automated testing without a graphical interface. It supports native engine extensions, allowing custom low-level code to be integrated into the core to expand functionality beyond the standard scripting interface. The

Mindustry is a cross-platform game engine and factory automation simulation that combines resource management with tower defense strategy. Players construct complex supply chains and automated networks to process materials while building defensive structures to protect a core from waves of hostile mechanical forces. The project utilizes a deterministic lockstep networking model to ensure simulation consistency across desktop and mobile devices. It is built on an entity-component-system architecture and a tile-based grid simulation, allowing for the efficient management of thousands of active

Hazel is a C++ game development framework and 3D graphics rendering engine designed for building high-performance interactive software. It provides a foundational architecture that enables the construction of desktop applications through native hardware acceleration. The project includes a dedicated game engine editor that allows for the design and testing of interactive 3D and 2D scenes within a unified environment. This editor utilizes an immediate mode interface to maintain synchronization with the engine state, while a hardware-agnostic abstraction layer handles rendering commands across

This project is a cross-platform game engine framework and build pipeline designed to produce playable executable binaries for desktop and Android devices. It provides a collection of core libraries for game development, including a native Android build system and a C++ build pipeline. The framework features a specialized bitmap font rendering system that displays stylized typography by mapping character indices to image atlases using coordinate and spacing metadata. It also implements a hardware abstraction layer to decouple application logic from graphics and audio drivers, ensuring portabl

OpenMW is a modern, open-source game engine designed to execute the game Morrowind and its expansions. It serves as a cross-platform game runtime and 3D world renderer, providing a data-driven environment to run game logic and physics with improved stability. The project functions as a game modding framework, utilizing a modular plugin system and an interpreted scripting layer to load external modifications. This architecture allows for the integration of community content, custom textures, and external scripts without altering the base executable code. The engine covers a broad range of cap

This project is an open-source 3D game engine designed for building high-fidelity games, simulations, and cinematic environments. It functions as a robotics simulation platform with native integration for ROS 2 to model robot controllers and sensors. The engine features a multi-threaded Forward+ physically based renderer that supports hardware-accelerated ray tracing and global illumination. The system is built on a modular extension architecture using Gems to add or replace features without modifying core binaries. It includes a native SDK for AWS cloud integration, enabling IAM authenticati

Unciv is an open-source, cross-platform turn-based strategy game and a community-driven remake of a commercial strategy title. It simulates empire building, city management, and technological research for players on Android and desktop platforms. The project is designed as a moddable game engine, allowing users to override gameplay rules, modify units and buildings via external definition files, and replace audiovisual assets. It supports the distribution of custom maps and the ability to import mod archives from remote web addresses. The application includes a dedicated server for multiplay

OpenSC2K is an open-source JavaScript city builder engine designed as a recreation of SimCity 2000. It functions as a web-based simulation that uses the Phaser 3 framework to implement game loops and entity management. The project utilizes WebGL and Canvas rendering to visualize large-scale urban environments. It includes a coordinate-based camera system that enables panning and zooming across the reconstructed game world. The engine incorporates a data pipeline to parse legacy city files and graphics assets, allowing it to reconstruct and display urban layouts within a modern web browser.

Godot is a multi-platform game engine and a suite of tools used to develop 2D and 3D interactive games and applications across multiple operating systems. It provides specialized development environments for both two-dimensional and three-dimensional design, including tools for sprite animation, tilemaps, lighting, meshes, and physics simulations. The engine includes a cross-platform export tool that packages projects for deployment to desktop, mobile, web, and console hardware targets from a single codebase. The system covers broad capabilities for interactive experience design and game dev

devilutionX is an open-source, cross-platform reimplementation of the original Diablo 1 game engine. It is a software framework designed to run the original action RPG logic and mechanics on modern operating systems by rewriting the engine in a current programming language. The project modernizes the legacy experience by adding support for widescreen resolutions, high-definition scaling, and configurable input mapping for various hardware controllers. It also introduces quality-of-life enhancements such as health bars, auto-loot, and tools to modify game speed and combat rules. The engine co

Battle for Wesnoth is an open-source turn-based strategy game set in a high fantasy world, built around hex-grid tactical combat. At its core, it is both a complete game and a game engine, offering single-player campaigns and multiplayer battles where players command faction-specific units across terrain that provides tactical advantages. The project is fundamentally a turn-based strategy game with a dedicated multiplayer platform, supporting online and local matches with replay recording and playback. What distinguishes Wesnoth is its deep commitment to custom content creation and modding. T

Dolphin is a software environment that simulates GameCube and Wii console hardware, allowing users to execute game discs and digital software on modern computing platforms. It functions by translating original console processor instructions into native host machine code at runtime and intercepting low-level graphics commands to render them through modern graphics APIs. The project distinguishes itself through a comprehensive netplay engine that enables online multiplayer for local games by synchronizing game states and input timing across remote instances. This system enforces deterministic e

Open Fodder: An open source port of Cannon Fodder

Source code of KeeperRL

Romanov's Vengeance is an OpenRA mod based on Red Alert 2.

NetHack is a roguelike dungeon crawler and ASCII-based role playing game. It is a turn-based adventure game featuring permanent character death and the exploration of randomly generated dungeons. The project serves as a cross-platform game engine designed to be compiled and run across diverse operating systems and hardware architectures. It focuses on retro game preservation by maintaining classic game logic for modern computing environments. The codebase implements procedural content generation for maps and encounters and utilizes a grid-based coordinate system for spatial tracking. Renderi

An Open Source Pixelart Science-Fiction Real-Time-Strategy game

Shattered Paradise's main repository and installation Kit.

Remake of Earth 2140 using OpenRA.

MegaGlest real-time strategy game engine (cross-platform, 3-d)