What's a song you would die to see live?

I was thinking about how Patrick Stump said Headfirst Slide into Cooperstown on a Bad Bet was out of his vocal range so he doesn't perform it live (there is 1 or 2 instances where he did perform live that I could find on YouTube) but I wish that wasn't the case because I love that song so badly. I was wondering if you had a song you would absolutely love to see performed live, especially a song that the band has explicitly stated they won't perform because that sucks even more