The Sensor Tower can spot enemy units in the fog of war, displaying them as a red symbol. Its range is visible to enemies on their mini-map and in-game, appearing as a large circle in the color of the player.
Top terran military analysts all agree that "Knowing is half the battle" and that early warning is one of the keys to victory. The sensor tower is a vital tool for long-range surveillance of enemy movement and the detection of stealthed aggressors. Sensor towers are a lynchpin of terran base defenses, and as such, they need to be heavily guarded. A smart attacker will try to destroy sensor towers as the first priority.
A sensor tower processes a whole battery of input, constantly updating a commander's knowledge of the battlefield. By using both passive and active thermal and electromagnetic scanning mixed with millimetric radar sweeps, input from seismic sensors, and Doppler analysis, a sensor tower can quickly pinpoint any target within range. Even foes that are out of sight behind terrain can be detected, although a visual verification will still be required to positively identify them.
The downside to all this multi-spectrum output is that foes can easily detect the presence of a sensor tower and use it to identify the whereabouts of a terran base. Other strategies revolve around "spoofing" the tower with decoy units or simply staying outside its range. Terran commanders have been known to counter by erecting sensor towers in fake base locations just to keep enemies guessing.
|| Radar  (passive)
| Effect Radius
| Used by || Sensor Tower
| Moving enemy units in the fog of war are marked with a red symbol. Does not detect cloaked or burrowed units.
The Sensor Tower was previously known as the Radar Tower. In older builds of the game, Missile Turrets depended on the Sensor Tower for detection, but have since gained their own detection.