- Allegro (C, zlib, mature)
- Annchienta (C++, GPL-3.0, mature, inactive since 2009)
- Arianne / Marauroa (Java, GPL-2.0, mature)
- Atlantis (C++, GPL-2.0, mature, inactive since 2016)
- Blender game engine (C++, GPL-2.0, mature)
- COCOS2D-X (C++, MIT, mature)
- Dash Engine (D, MIT, mature, inactive since 2015)
- Delta Engine (C#, Apache-2.0, mature, inactive since 2015)
- ENIGMA (C++, C, GPL-3.0, mature)
- EasyRPG Player (C++, GPL-3.0, mature)
- Flare Engine (C++, GPL-3.0, mature)
- Flixel (ActionScript, MIT, mature)
- GemRB (C++, Python, GPL-2.0, mature)
- Godot (C, C++, MIT, mature)
- H-World (C, Lua, GPL-2.0, beta, inactive since 2005)
- HaxeFlixel (Haxe, MIT, mature)
- Irrlicht Engine (C++, C, zlib, mature)
- JiGS Interactive Game System (JavaScript, PHP, GPL-3.0, beta)
- Lightweight Java Game Library (Kotlin, C, 3-clause BSD, mature)
- Lumix Engine (C++, MIT, beta)
- LÖVE (C++, zlib, mature)
- Mana (C++, GPL-2.0, beta)
- Maratis (C++, GPL-2.0, beta)
- Minetest (C++, Lua, LGPL-2.1, mature)
- MonoGame (C#, MPL, MIT, mature)
- O.H.R.RPG.C.E (Basic, GPL-2.0, mature)
- OGRE3D (C++, MIT, mature)
- Octaforge (C++, Custom, mature)
- Open RPG Maker (C++, GPL-3.0, beta, inactive since 2014)
- OpenFL (Haxe, MIT, mature)
- OpenRPG (Python, GPL-2.0, mature, inactive since 2013)
- Orx (C, zlib, mature)
- Panda 3D (C++, C, 3-clause BSD, mature)
- Polycode (C, C++, MIT, beta)
- Qt (C++, LGPL-3.0, mature)
- Quad-engine (Pascal, MIT, beta)
- SDL Game Engine 2D (C, MIT, beta, inactive since 2014)
- ScummVM (C++, GPL-2.0, mature)
- Solarus (C++, GPL-3.0, mature)
- Superpowers (Typescript, ISC, mature)
- Terasology (Java, Apache-2.0, mature)
- Urho3D (C++, AngelScript, MIT, mature)
- Vega Strike (C++, GPL-2.0, mature)
- WorldForge (C++, GPL-2.0, mature)
- ZGameEditor (Pascal, MIT, mature)
- jMonkeyEngine (Java, 3-clause BSD, mature)
- libGDX (Java, C++, C, Apache-2.0, mature)
- mkxp (C++, C, GPL-2.0, mature)
- pyORPG (Python, MIT, beta, inactive since 2015)
- pygame (C, Python, LGPL-2.1, mature)
- rpge (C, GPL-3.0, beta, inactive since 2014)
- sandbox Game Maker (C++, C, Custom, mature, inactive since 2014)
- xoreos (C++, GPL-3.0, beta)