Many of you may have experienced Zerglings runby through building gaps that you think the Zerglings cannot get through. The following video explains how to wall.

I did not make the video, so credit of video goes to the owner.

Walling off technique is not exactly new, but I find this video pretty well done. The purpose of this post is simply to “transcript” the video into images and words. I find it easier to refer to images and words than videos for building placement guide.

Click to enlarge images.

Three plus two types of buildings

– 2×2
– 3×3
– 5×5
– Spore Crawler* (Spine Crawler too?)
– Vespene Geyser

Spore Crawler is a 2×2 building, but it works in a unique way. Although the video mentions only Spore Crawler as the unique 2×2 building, Liquipedia states that Spine Crawler works the same way as Spore Crawler.

Vespene Geyser (Refinery, Assimilator and Extractor) is a 3×3 building, but it also works in a unique way.

2×2 Buildings

– Supply Depot
– Missile Turret
– Sensor Tower

– Pylon
– Photon Cannon
– Dark Shrine

– Spire
– Spine Crawler
– Spore Crawler*

3×3 Buildings

– Refinery*
– Barracks
– Engineering Bay
– Bunker
– Factory
– Ghost Academy
– Armory
– Starport
– Fusion Core

– Assimilator*
– Gateway
– Forge
– Cybernetics Core
– Twilight Council
– Robotics Facility
– Stargate
– Templar Archives
– Robotics Bay
– Fleet Beacon

– Extractor*
– Spawning Pool
– Evolution Chamber
– Roach Warren
– Baneling Nest
– Hydralisk Den
– Infestation Pit
– Nydus Network
– Ultralisk Cavern

5×5 Buildings

– Command Centre

– Nexus

– Hatchery

Three sizes of units

Small

– SCV
– Marine
– Reaper
– Ghost
– Marauder
– Viking (Assault mode)

– Drone
– Zergling
– Baneling
– Hydralisk

– Probe
– Zealot
– Sentry
– Dark Templar
– High Templar

Medium

– Widow Mine
– Hellion
– Hellbat

– Roach
– Infestor
– Swarm Host

– Stalker
– Immortal
– Colossus

Large

– Tank
– Thor

– Ultralisk

– Archon

Three types of wall

– Solid wall: No units get through
– Hard wall: Only small units get through
– Soft wall: Only small and medium units get through

2×2 and 3×3 buildings work in the same way. One adjacent square is enough to form a solid wall.

Wall diagonally will form a hard wall.

One square apart will form a soft wall.

5×5 buildings require two adjacent squares for solid wall.

One adjacent square will form a hard wall.

Wall diagonally will result in no wall off. That is, any units can get through.

Two adjacent Spore Crawlers make a hard wall. Diagonal Spore Crawlers make a soft wall.

Mineral patches form solid wall with both adjacent and diagonal wall.

Vespene Geyser forms soft wall with diagonal wall.

Top and bottom of a ramp have different wall off requirement. The image below illustrates better than words. Grey is the ramp. Top right is top of ramp and Bottom left is bottom of ramp. The red squares are not required for bottom ramp wall, but are required for top ramp wall.

Leave a comment if you know whether Spine Crawler works the same way as Spore Crawler.

EDIT: Spine crawler does not work the same way as Spore Crawler.