It Came from the Nightosphere
Marceline and Amanda were backstage at the beginning getting set up and were the first band on stage. They played songs! They weren't terrible! Some of the songs were even new! They've got a sort of Anti-White Stripes thing going on. Amanda's drum beats weren't minimalistic but clever. Marceline's bass varied between understated to fast and furious, emphasizing those sweet vocals. After their set, Marceline went to mingle in the crowd and find her boyfriend.
Of note: Marceline wasn't playing her usual axe bass, instead using a red, four-string Fender 1951 Precision Bass with covers on the pickup and bridge and two knobs, one for volume and one for tone and a slightly larger pickguard. Her feet were also firmly on the ground for the show, but damn does the girl have hops when she jumps around on stage.