If you're talking about pulling exotic armor from your Collections, these have a fixed roll. If you want different rolls, you have several options if you're specifically looking for exotics: - Purchase different exotic armor rolls from Xur directly each weekend - Purchase an Exotic Engram from Xur for a random exotic (with random rolls on armor) - Complete Legend/Master Lost Sectors solo for a chance at an exotic in a specified slot - Complete Nightfall: The Ordeals for a chance at a random exotic