How to hide Assembly-CSharp.dll ?

Unity games typically store their compiled code, "Assembly-CSharp.dll" and "Assembly-CSharp-firstpass.dll", in the "<GameName>_Data/Managed" directory.

However, then there is INSIDE, which does not contain those dll's.

I wonder how I can do that as well. Any idea how to "hide" those dll files?

 

IL2CPP and a custom build, I would guess.

 

They may have used something like Enigma Protector, which puts all your game files/folders into a single virtual machine .exe, which makes it really tough to hack/crack/view etc.