Three times now my group have detonated all 16 black orbs at once and failed to kill Oryx. Twice he took like no damage (a small amount, less than what you'd do with 4 orbs) and once he took NO damage. WTF Bungie. This challenge mode has some serious issues. Just wasted several hours of my life for no rewards. In addition to this, we had to wipe on several occasions because the Ogres decided to teleport from beside the pillars to the main walkway... What's going on!?! Fix your s**t.