godot-dotnet : Multi-platform 2D and 3D game engine with a feature-rich editor ( https://godotengine.org/ )
surgescript : scripting language made for opensurge ( https://alemart.github.io/surgescript )
unityhub : Official Unity tool for managing Unity Engines and projects ( https://unity.com )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a guru
For Paludis use this rsync : rsync://gentoo.zugaina.org/guru-portage
If you have a problem : ycarus(-at-)zugaina.org