Firebase and Unity 3D.

Even is an old feature the Google team comes with this new option for the new developers and show how to use them.
The goal is to add Firebase to your Unity project.
The Google webpage tells us:
Power up your Unity games with our Firebase Unity SDKs. To show how easy it is to plug Firebase into your Unity project, we made a sample game, MechaHamster, that you can download from GitHub, the App Store, and the Google Play Store.
... and show a short video about how can be used to create a application named Mecha Hamster, see the GitHub webpage project:
You can import the project with GitHub commands:

https://github.com/google/mechahamster.git
...

The game is pretty funny, see the Youtube channel from Firebase:

The content of the folder downloaded ...

$ ls
Assets   CONTRIBUTING.txt  LICENSE.txt      readme.md  UnityPackageManager
console  docs              ProjectSettings  Resources