This glitch was supposed to be kept a secret between me and my friend but since this glitch hasn't been spread yet i'll tell you this is a really old glitch. Okay first of all in horde pick wave 10 on Gridlock then get a boom shield and place it on the stairs after when you see a bloodmount kill the locust that's riding him but don't kill the bloodmount instead let him live just mantle over the shield and you should land on his back. Once your on him he will start to run around with you on him theres no way to get off of him you can't even shoot him so you'll just have to throw a grenade it won't kill you but you'll be downed but not out, or have a teammate shoot him and that's it i don't know if this glitch was fixed by the fourth title update but you can still try it.