It is important to clarify upfront: does not correspond to a known mainstream song, album, or public figure based on standard German music or pop culture databases (as of my latest update).

However, the phrase itself carries a very distinct, authentic ring of German urban youth slang , mixed with a personal dedication. It translates loosely to: Adding “full” at the end (from English “full” used as German youth slang for “really/absolutely”) suggests emphasis, like “voll” in German but written in Denglish style.

So whether you are Natascha, “Alter,” or just a curious German learner: Du bist auch die beste – Alter full.