Motion tracker

Spartans and Elites have a Motion Tracking Sensor built into the HUD of their helmets and armor. The sensor shows friendlies as yellow blips and friendly vehicles as large yellow blips. Enemies are shown as red blips, Hunters and enemy vehicles as large red blips. Flood Infection Forms are shown as small red blips, except in the level The Covenant, when they are allies. They are then shown as small yellow blips. The motion tracker will show how close they are in relation to your current position, up to 25 meters. When someone on the other team in multiplayer speaks, their red blip is surrounded by a white glow and it becomes bigger. Nav points will also show up, shown only as a small white triangle at the end of the sensor.

The motion tracker is not a radar. Slow moving enemies will not show up on the sensor. This can work to your advantage of course, moving very slowly or crouch walking will mean you won't show up on enemies motion trackers. This cuts two ways, since you can't see crouching enemies on your motion tracker.

Trivia

 * In Halo 3 custom games or Forge, the motion sensor can be increased its range by 15 metres, 25 metres, 50 metres or even 150 metres.


 * The Motion Tracker may be homage to the movie Aliens, as these are used to both detect and track the creatures but have one fatal flaw that is carried on to the Halo version; it doesn't show depth, you can't tell if an enemy is either above or below you.


 * In the novel Halo: Ghosts of Onyx, the motion tracker sensor is shown to be vulnerable to sea water, when Fred's motion tracker froze due to a crusting of sea salt.