CTFs as you need them
Desktop/Android/HTML5/iOS Java game development framework
Unity3D Client And C# Server Framework
Gideros Release version
All-In-One program that combines multiple Fortnite Dev Account tools.
Game engine supporting many 3D/2D formats and graphic effects
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
Modern 3D engine and IDE written using C# and C++.
Example code for creating a 2D platform game in Java.
Build Cross-platform Applications
3D .NET engine for Windows, Linux, Mac
Open Game Bootstrap
Mahasona engine is an open source game engine.
Built to be ease of use, with no programming knowledge, Multi-platform
A tool for editing OHRRPGCE RPG files
UtiliGame is a light-weight game engine written in Java.
AdventureMap peripherals for ComputerCraft
The classic intelligent role playing game
AMOS BASIC reimplementation in Java
Cross-platform 2D game engine