Knights is an achievement in Halo: The Master Chief Collection. It is awarded for activating the fifth Halo 4 Terminal on Shutdown. The achievement is worth 5 gamerpoints and can be unlocked on any difficulty.
In the third spire, get to the central platform with multiple light bridges. Cross the light bridge to the left of the bridge you would normally cross to reach your objective. This leads to a platform guarded by Jackals. The Terminal is located behind the platform's central column.