Banshee looks up from his work as you approach. "Hey," he says. "Heard about the Moon. Nightmares. Vex." He shakes his head. "You're gonna want some, uh... Some real firepower for that."
His gaze loses focus for a moment, then he goes on. "Got somethin' in my workshop that I want you to have. Ain't a gun. Big Bow. It'll chew up those Vex real good. You go on up to my workshop, take a look at it. See if you like it. Cayde'll tell ya where the secret entrance is."
Another customer queues behind you. Best get going.