Sight Blockers

[e][h] Line of Sight Blocker

Unit Information

Type:

Doodad

Description:

Blocks line of sight for ground units.

Unit stats

Defense:

0 1

Sight Blockers or "Line-of-sight(LOS) Blockers" are a feature on some StarCraft II maps. They manifest themselves as High Grass or Smoke Billows that hide whatever is behind it from sight: your units need to walk through them to see what's on the other side. Sight Blockers can be used to lay an ambush or to hide units. On some maps like Metalopolis and Scrap Station a small part of your base is hidden from sight - a popular place for hiding proxies.

Sight Blockers can have different appearances, such as tall grass, or exhaust fumes. The different appearances do not change their function.

Sight Blockers prevent ground units on one side from seeing anything past their vertical plane. Air units are unaffected, and ground units are only affected by sight blockers if the controlling player does not otherwise have vision of the opposite side.

Notable Uses

• As mentioned, many mains have a corner sanctioned off by LOS blockers, providing good spots for Nydus Worms, drops, early game proxies, and many other strategies. The player the main belongs to sees everything as normal unless they have a unit/building inside the LOS blocked region.

• Sight Blockers in the open field can be useful for melee or short ranged units that need to close in on long ranged units. An example would be camping a Zealot army next to the closest Xel'Naga Tower (this area is enclosed by gas vents that act as LOS blockers), knowing that the enemy Marauder force will take that route to get to your base. The Marauders only start shooting the Zealots once they have gone into the vents and seen them, at that time, the Zealots are already on top of the Marauders, and the Zealots have a fighting chance.

• Conversely, LOS Blockers are also useful for long ranged units because in SC2 you are not given sight to the enemy units that attack you. Placing Siege Tanks behind sight blockers means opposing ranged units like Hydralisks need to walk all the way up to the siege line before they can see the tanks to fight back, by that time they should be dead.

• Sight Blockers provide an optimal spot for Banelings. The Banelings can't be seen until it is too late and the enemy forces are right on top of them. Of course, once the Banelings have burrow, this can be accomplished anywhere.