When you first launched Minetest, didn't you think it was just Minecraft? Actually not. Although their interface, style, and gameplay are almost the same, Minetest is essentially a free, open-source and cross-platform voxel game engine (written in C++ and Lua, using the Irrlicht Engine). It was created by Perttu Ahola and first released in 2010, and is now developed by a team of volunteers, with significant contributions from the community. It's available for Linux-based systems, FreeBSD, Windows, Mac, and Android platforms, and provides an API for users to create their own games and mods written in Lua.

Mario Editor is the latest, free Mario game platformer/level editor created by Hello Fangaming in 2016, using the GameMaker: Studio game engine. Meanwhile, it's also the successor of the Super Mario Bros: Game Master, and serves as the celebration of the 10th anniversary of the famous and popular open-source project: Hello Mario Engine.

Torque 3D (full name: Torque Game Engine, TGE for short) is free, open-source and cross-platform 3D game engine developed by GarageGames (originally developed by Dynamix for the first-person shooter game Tribes 2 released in 2001) under the MIT license. It features powerful and complex rendering system, high-speed network transmission, authentic real-time editing, script editing system, as well as maximum flexibility and performance across a wide-range of hardware, and a full suite of tools for producing high-quality Windows and browser-based games development.

BuildBox is the world's first real sense of foolproof game making tool (founded by Trey Smith in 2014). Because in BuildBox, the entire game development process can be done simply by dragging and dropping operations, no coding, scripting, programming or software design experience required. It's specially developed for entrepreneurs, designers and other game creation enthusiasts without any program development foundation for game design.

As is known to all, all the time, the most popular RPG game production tool must have been none other than RPG Maker. But from now it needs to try its best to keep its job. Because it has had a brand-new and foolproof game engine that can produce both 2D and 3D RPG games with ease as its strong competitor - SMILE GAME BUILDER, which is currently the only 3D RPG game making software as I know (without regard to using the general 3D game development engines, such as Unity, Unreal Engine, etc.).