Zepter translates to "scepter", a ceremonial staff held by a monarch as a symbol of authority. It's a regal and somewhat archaic word, making it stand out in a rap song.
Bushido uses this word to assert his dominance and long-standing reign in the German rap scene. He repeatedly states, "Weil ich dieses gottverdammte Zepter in der Hand hab'" (Because I have this goddamn scepter in my hand), emphasizing his undisputed power and control over the genre.
Bushido's "Untouched" is a full-on flex, a declaration that he's in a league of his own and completely untouchable in the German rap scene. He's basically saying, "Forget your league, man, I play in my own" [Scheiß auf deine Liga, Mann, ich spiel' in meiner eigenen]. He sees himself as the original, the trendsetter, claiming that other rappers are just copying his style, his beard, even his tattoos. He's the OG, the "Gangsterrap-Millionär," and he's not shy about it.
He really drives home the point that he's the one with the power, the captain of the team, like Tsubasa with the number ten jersey. He even brags that when he calls, "every German rapper sounds like my groupie" [Hört sich jeder deutsche Rapper wie mein Groupie an]. Bushido believes he set the 90bpm trend and that he's the one who will be rapping until the end, because he holds the scepter. He's confident that no matter how much others try to curse him or bring him down, he remains "untouched."