Finally got Godot 3 with Mono support built on Arch Linux!
Pro-tip: Install "msbuild-stable" from AUR & "mono" from standard repo. Use this PKGBUILD for Godot: https://pastebin.com/GmN9Pxhr
Also, make sure "GodotSharpTools.dll" is copied to live beside the "Godot" executable in /us/bin. Had many crashes when trying to attach a C# script to a Node due to this.
Now time to make stuff...
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