MonoGame

Defold is a free and open source game engine designed for high-performance cross-platform game development. It comes fully featured out of the box, requiring no setup or configuration, allowing developers to simply download the editor and start creating. The engine includes a visual editor, code editor, Lua scripting, Lua debugger, scene editor, particle editor, and tilemap editor, and supports both 2D and 3D game development. With a single codebase and no need for external tools, Defold enables publishing to major platforms such as PlayStation5, PlayStation4, Nintendo Switch, Android, iOS, macOS, Linux, Windows, Steam, HTML5, and Facebook. It offers a component-based system for building games, allowing the use of basic building blocks to create complex behavior, and supports writing game logic using Lua. Developers can add new functionality from the asset portal, set up their own local build environment, and write native code to extend the engine.

raylib is a simple and easy-to-use library to enjoy video game programming. It is a programming library to enjoy video game programming; no fancy interface, no visual helpers, no GUI tools or editors, just coding in a pure spartan-programmers way. raylib does not provide the typical API documentation or a big set of tutorials. The library is designed to be minimalistic and be learned just from a cheat sheet with all required functionality and a big collection of examples to see how to use that functionality. The best way to learn to code is by reading code. raylib supports multiple target platforms, it has been tested in the following ones but, technically, any platform that supports C language and OpenGL graphics (or similar) can run raylib or it can be very easily ported to. You can use raylib with multiple programming languages, there are over 60 bindings. raylib can be combined with several extra libraries for additional functionality.