Conor McGregor threatened Khabib Nurmagomedov and Justin Gaethje in an explosive Twitter rant on Monday.
McGregor, 31, was last in action in January, but is seemingly ready for a return, even if it is behind closed doors due to the coronavirus pandemic.
The Irishman blasted both Khabib, the unbeaten lightweight champion, and Gaethje, who beat Tony Ferguson on Saturday.
"The fans make the sport! Watching the other night I was against going in without them," McGregor wrote on Twitter.
"But it will be my f****** pleasure to display the power I possess with zero background noise for them. Its [sic] me and Justin next as khabib is the biggest bottle fighter in the game. Guarantee it."
McGregor continued: "Justin, there is no danger in a man that hugs legs, we all know. Try and dance around what the real threat is here all you want. I am going to f****** butcher you. Your teeth. I'm going to put them on a f****** necklace. Speak on my skills as a father? You are f****** dead."
"Khabib you absolute embarrassment. Scurrying, hiding rat as usual. As I have said many times. As has been seen many times," McGregor continued.
"Through the pane of glass it was confirmed what was always known. "No comment" lol. An embarrassment to real fighting."
Khabib beat McGregor in an infamous bout in Las Vegas in October 2018, and is 28-0.
The Russian hit back on Twitter, and alongside a photo of their fight wrote: "Yes, we remember you, you was so nice that night, be same, don't be fake."