Godot is an open source game engine which is very accessible to pickup and use. It's especially awesome for building 2D games. I've made a couple of hyper casual games using it and it was a fun experience building them.
The best part is Godot engine can export to all the platforms you expect Windows, Linux, MacOS, Android, IOS and Web (HTML5). I've hosted my games on gotm.io, the best part is they work on mobile as well :)
You can check out the source code if you want to play around:
(github.com) https://github.com/vkbsb/DotDot
