A Gas Steal means you block your opponent's Vespene Geyser by placing one of your own extraction buildings on top of it. This is typically performed in the early game, denying the opponent their initial Gas production. This can potentially devastate an opponent early on, since it may interrupt their build order. It is commonly used in PvP to force a 4 gate. Further, if the opponent has not yet produced combat units then workers are sent to destroy the building, leading to lost Mineral income and delayed Gas income.
Protoss is perhaps the best at gas stealing because a Probe can keep moving after it starts warping in an Assimilator. Terran on the other hand is at a disadvantage because an SCV has to stay to do the construction work and can be killed while doing so. Gas stealing as Zerg is generally seen as a no-lose situation. Many players see that the drone is likely to die anyway once the scout is over, so it may as well gas steal. Some players repeatedly cancel and rebuild their Extractor to prolong the time the gas is stolen for and forcing the opponent (specifically Terrans or Zerg) to get more units to kill the Gas Steal.
Effectiveness of Gas Stealing
Generally, two are the possible advantages of stealing an opponent's gas:
- It forces your opponent to pull units away from their choke to kill the building. This lack of defense in your opponent's front can either be exploited if you plan to commit to an early attack or even to allow you to get a second scout in their base, if you feel you have to scout again to see an important part of their build.
- It delays their tech. This may initially seem advantageous in every situation but you need to keep in mind that your own tech/unit production will also be delayed due to the minerals spent on the Assimilator/Refinery/Extractor. The following factors should be considered before deciding to steal the opponent's gas:
- The build you intend to perform and possible weaknesses it may have to fast tech openings
- The starting locations in order to decide if these "tech builds" are a possible and effective choice for your opponent.
For example a Protoss player at 12 o'clock on Lost Temple that wants to go for a build that gets a rather late Robotics Facility against a Terran on 2 o'clock may want to steal their gas to prevent or delay them from teching to cloaked Banshees since your opponent will lack detection early on.
On the other hand a Protoss player that is two gate rushing their opponent will not benefit from a Gas Steal not only because they need as many minerals as possible, but also because if the opponent is allowed to go up the tech tree your opponent will have fewer units defending against the incoming Zealots.
- oGs???? vs HyperDub in XPT Team Tournament.