Catalysts are one of my favourite additions. It makes me use an exotic I normally wouldn't and have fun and get to grips with it. Also gives me something to focus on. I'm using Jade Rabbit in pvp and Polaris in pve at the moment. Did the Tractor Cannon, Colony, Vigilance Wing, Crimson, D.A.R.C.I, Botealis, Fighting Lion and Sturm. Annoying I can't finish the Sweet Business one and I cannot get the Huckleberry one to drop. Catalysts for all exotic weapons please.