In the Vanced Context
Vanced MicroG was the specific version used with YouTube Vanced. It is discontinued and no longer maintained.
In the ReVanced Context
GmsCore is the actively maintained version used with ReVanced for non-root installations. It is available from the official ReVanced GitHub repository.
MicroG (now called GmsCore in the ReVanced ecosystem) is a lightweight, open-source implementation of Google's proprietary framework APIs. It enables Google account features - sign-in, notifications, and sync - in apps that are installed outside Google Play without requiring root access or full Google Play Services.
In the Vanced Context
Vanced MicroG was the specific version used with YouTube Vanced. It is discontinued and no longer maintained.
In the ReVanced Context
GmsCore is the actively maintained version used with ReVanced for non-root installations. It is available from the official ReVanced GitHub repository.