OGRE

Godot provides a huge set of common tools, so you can just focus on making your game without reinventing the wheel. Godot is completely free and open-source under the very permissive MIT license. No strings attached, no royalties, nothing. Your game is yours, down to the last line of engine code. Nodes for all your needs. Godot comes with hundreds of built-in nodes that make game design a breeze. You can also create your own for custom behaviors, editors and much more. Flexible scene system. Create node compositions with support for instancing and inheritance. Visual editor with all the tools you need packed into a beautiful and uncluttered context-sensitive UI. Friendly content creation pipeline for artists, level designers, animators and everyone in between. Persistent live editing where changes are not lost after stopping the game. It even works on mobile devices! Create your own custom tools with ease using the incredible tool system.