Definition [ edit ]

Two areas of terrain that are separated by a combination of cliffs and/or ramps are called high ground or low ground in relation to each other. The distinction between the two is important, as the high ground has several benefits over low.

Mechanics [ edit ]

Summary [ edit ]

Notwithstanding limits set by sight radius, attack range and attack type:

High ground Any Unit on high ground can see any unit on the low ground. Units on the high ground that attack will reveal their position.(but not necessarily grant vision)

Low ground Ground Units on the low ground can not see ground units on the high ground. Ground Units on the low ground can only see air units on the high ground if the air unit has attacked them. Ground Units at the bottom of a ramp have reduced vision up the ramp.



These mechanics are described as the high ground advantage. Units on low ground can be ambushed and cannot counterattack unless vision is gained of the high ground by moving an air unit or Colossus into range, utilizing a Xel'Naga Tower or a Scan with vision of the high ground, or by moving a friendly ground unit onto the high ground within vision range.

It is important to note that air units do not receive the full high ground advantage. Air unit movement can be hidden by keeping them over high ground, but they will be revealed if they attack any enemy unit.

Details [ edit ]

The Terran player cannot see any enemy movement on the high ground above. The Colossus can see the Siege Tanks below, but it will remain unseen until it attacks.

Terran view from low ground. Protoss view from high ground.



The Stalker can attack the Terran forces below without being counterattacked. Its position is displayed in the sense that it appears greyed out underneath the fog of war, but it is not revealed in the sense that the Terran troops can attack it. The Terran player cannot see the Void Ray because it has not attacked.

Terran view from low ground. Protoss view from high ground.

A Void Ray is now attacking the Bunker. Whereas the Stalker is displayed but can't be attacked, the Void Ray is revealed and is taking damage in turn. Air units can ambush from high ground to get the first shot, but may then be counterattacked. An air unit is revealed by any action that directly affects the enemy. The Phoenix is not damaging the Siege Tank but has been revealed by affecting it. Actions that do not directly affect the enemy do not reveal air units. The Stalker is not directly affected by the Medivac so can see and attack the Marine only.

The Void Ray is counterattacked. The Stalker remains untargetable. A Phoenix takes fire. Healing from high ground.

Prior to Patch 1.4, a special case existed with the Broodlord and the high ground mechanic.[1] [2]The Broodlord was not revealed and could not be attacked even when shooting Broodlings at enemy units.

The Mutalisk and Carrier are both revealed but the Broodlord remains hidden.

Since Colossi are tall enough to be counted as air units as well as ground, they are treated as air units for the high/low ground mechanic. Here, the Colossus will get the first shot, but can then be attacked by the siege tanks. In the second picture, a Stalker, who would normally be safe on high ground, takes splash damage from the Siege Tanks attacks on the Colossus.

A Colossus attacks from high ground. A Colossus and Stalker take damage.

Delayed attacks show how air units are revealed when they affect the enemy, not during any cooldown or delay that may proceed an attack. The Stalkers below cannot see the Raven on the high ground. When a Hunter Seeker Missile is fired the Raven's position is displayed. Only when the missile has exploded is the Raven revealed and vulnerable to counterattack. Note how the brightness of the Raven changes from displayed to revealed. If the Raven had moved out of range while the missile was flying it would have been revealed no matter how far it went, but it would not have been counterattacked. This mechanic can be used by Carriers which can pull back slightly after launching Interceptors.

Stalker's view of low ground. Raven fires HSM. Stalkers counterattack.

Use [ edit ]

High ground is especially useful in the early game for defending one's ramp. A Protoss can Force Field a ramp to prevent vision, forcing the aggressor to bring a "spotter" air unit or use a Scan.

When Terran has Siege Mode, he can siege his tanks close to the cliff and use either a spotter or a Scan to fire onto buildings or even in some cases the opponent's mineral line.

Also effective can be any kind of drops onto the high ground close to a mineral line on the low ground. Lost Temple was famous for high ground Tank/Thor drops, which prevented mining and, if not reacted to quickly enough, could snipe a Hatchery or Nexus.

Tank drop on Lost Temple Spotting the high ground with an Observer