Doctor wasn't foolish enough to enter this fight without an instrument in hand or in this case an electric guitar that had either been hiding under his coat or in a pocket that was bigger on the inside. He joins the musical duel backing up Luce's song and adding a dramatic flare between her verses (Beethoven's Fifth?). Lights begin flickering and surround him and Luce. Bringing sunglasses had been a good idea indeed.

"He may go by Mr. Universe but as it turns out I've seen a lot more stars than he has." Doctor jokes. It might just be Luce's flame making him feel so confident but somehow Doctor doubts Greg could beat him in a competition of stars of all things.