Os dejo éste listado de motores de videojuegos, espero que os ayude a probar cuantos más mejor.
Adventure Game Studio
Aleph One
Allegro library
Angel2D
Anura
Ardor3D
Axiom Engine
Blender
Build engine
Cafu Engine
ClanLib
Cocos2d, Cocos2d-x, Cocos2d-html5
Construct Classic
Core3D
Craftstudio
Crystal Space
Cube
Cube 2
Delta3D
Dim3
DimensioneX Multiplayer Engine
Duality
Eclipse Origins
ENIGMA
Env3D
Exult
FLARE
Flexible Isometric Free Engine
Flixel
Game Closure
GameKit (OgreKit)
GamePlay3D
Gamvas
Godot
Grit
Haaf's Game Engine (HGE)
HaxeFlixel
HGamer3D
Horde3D
HPL 1 engine
id Tech 1 (Doom)
id Tech 2 (Quake)
id Tech 2 (Quake II)
id Tech 3
id Tech 4
Indielib
ioquake3
IwGame Engine
Jake2
JGame
jMonkeyEngine
Jogre
Kobold2D
Kiwi.js
LibGDX
LÖVE
Magnum
Maratis
Marmalade SDK
kivy
Moai SDK
Multiverse Foundation
Nebula Device
Ness-Engine
NetGore
NME
nxPascal
Ogre3D
ONScripter
OpenSimulator
ORX
Oxygine
Panda3D
Pixel Dust Game Engine (PDG)
PixelLight
PlayCanvas
playn
Polycode
PLIB
Pyrogenesis
Ren'Py
Retribution Engine
SFML
Sge2d
Spring
Starling Framework
StepMania
Stratagus
Torque3D
Turbulenz
Urho3D
Wire3D
WorldForge
ZenGL
ZGameEditor
Name¿Has probado alguno de éstos motores? ¿Te interesaría que habláramos de alguno de ellos?