Cocos simplifies game creation and distribution with Cocos Creator, a free, open-source, cross-platform game engine. Empowering millions of developers to create high-performance, engaging 2D/3D games and instant web entertainment.

F1 Tycoon/Manager Game in JavaScript. This project is a Formula 1 team management game, drawing inspiration from Cockpit Manager and Brasfoot.

A fast C++20 3D game engine for modern devices, with wide platform support

An Open Source Voxel RPG

3D game programming and rapid prototyping library.

A historical stealth game set in Cebu during Marcos Sr.'s regime, educating players on activist struggles through game and historical storytelling.

The Dæmon game engine. With some bits of ioq3 and XreaL.

Players can operate turret to defend against waves of enemies which they have complete control over within Unity Inspector. Including projectile and fire rate control, animation control, damage and health control, etc.

A simple game engine designed to build board games. Started as a learning project and should remain as is in the future.

Godot Engine – Multi-platform 2D and 3D game engine

Next-gen general purpose game engine written in modern C++

Simple small game inspired by QIX for testing GTK 4

RavEngine sample programs

AllBinary Game Development Kit (HTML5 Examples: https://html5.allbinary.com), Freeblisket E-Commerce Solution (https://allbinary.com), AllBinary Input Automation, and everything else AllBinary. It represents >10 years of development and > 1 million SLOC. The main goal of the AllBinary Platform is to help people escape the tyrants of earth.

Open Source real-time strategy game engine for early Westwood games such as Command & Conquer: Red Alert written in C# using SDL and OpenGL. Runs on Windows, Linux, *BSD and Mac OS X.

ZQuest Classic is a game engine for creating games similar to the original NES Zelda

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fheroes2 is a recreation of Heroes of Might and Magic II game engine.

A wonderful list of Game Development resources.

Generate unique, solvable maze for users to solve within a specified time frame.