Remove the Bishops From the Board Achievement in Halo: The Master Chief Collection

Promethean Watchers are a highly advanced Forerunner A.I. that will only appear in Halo 4. Serving as defense units for Promethean Knights, you can always spot these pesky enemies hovering above their masters. In fact, Knights are the sole source of their spawn, via the carapace on the Knight’s back.

Given their guardian-like nature, they will prove to be very stubborn in battle. They provide covering support with Boltshots, project Hardlight Shields onto Knights, and even revive destroyed Knights in the midst of battle. If that wasn’t enough to prove their worth, Watchers will also redirect any thrown grenades back to you via a gravity displacement beam. With this mind, make sure to take on Watchers from afar with steady-shot weapons such as a Carbine or Battle Rifle. Getting rid of them early in battle will be necessary before focusing your attention on other enemies.

A perfect opportunity to grind out Watcher kills would be during the final mission of the Campaign, Midnight. From the Campaign lobby, go ahead and load up Rally Point Bravo on the aforementioned mission. As you run up the ramp and through the door into the next hallway, there will be four Watchers in this large chamber. You can opt to kill all four with your precision weapon, then reload the checkpoint to grind out the kills. Remember, these Promethean enemies only appear in Halo 4. Once you have killed a total of 1,000 Watchers, this achievement will unlock.