On Eminem's surprise album Music to Be Murdered By, Eminem addresses and dismisses Machine Gun Kelly on his Young M.A featured track "Unaccommodating."

"But when they ask me is the war finished with MGK? Of course it is
I cleansed him of his mortal sins, I'm God and the Lord forgives even the devil worshippers
I'm moving on but you know your scruples are gone when you're born with Lucifer's horns
And you're from the school of Notorious, Puba, Cube and The Poor Righteous Teachers tutored my students
Showed them all the blueprint and formula
But it seems like the more they studied my music, the more they remind me of eyeballs
I'm watching my pupils get cornier," Em raps.

After hearing the track, MGK jumped on Twitter and suggested he wants more smoke.

mad af I just stepped out a loud room to hear this bullshit ?

— colson (@machinegunkelly) January 17, 2020

he’s been rich and mad for 20 years straight. ??

— colson (@machinegunkelly) January 17, 2020

"Mad af I just stepped out a loud room to hear this bullshit," MGK typed. "He’s been rich and mad for 20 years straight."

Kelly's next album is a pop-punk effort with Travis Barker.  Are you allowed to address rap beef on a punk album?