An enterprising gamer seems to have discovered a Starcraft 2 exploit with game breaking consequences, at least at the competitive level. And it’s likely been in the game since it’s launch in 2010.
The exploit allows you to scout your enemy’s position by taking advantage of the game’s pathing algorithm.
If you rally a worker to a mineral patch, it’ll automatically shift the path to the nearest unworked mineral patch, if the original target is already mined by a worker. That helps streamline mining in your base—you can rally new workers to one mineral patch, but get efficient mining since they’ll automatically move to open patches instead of losing your minerals by getting in each other’s way.
But if you rally to a patch in your opponent’s base, the path will still be optimized. Despite their mining operation being hidden by the fog of war. If your worker’s path switches from the rally target, you’ve discovered a patch where your opponent is mining. It’s easy to choose a worked mineral patch, because mineral patches are not a uniform distance from a base, it’s efficient to mine the closest ones.
It’s a simple trick with huge implications.
Information is the lifeblood of Starcraft. Knowing more than your opponent is the difference between winning and losing. Scouting is the basis of building to counter your opponent or properly executing an aggressive build.
Locating your opponent early allows you to send a scout quickly without wasting time checking other spawn points, giving you precious information much sooner than you normally would on larger map. It could allow you to execute a super-fast rush with certainty of the opponent’s location, making some aggressive builds like 10 pools more viable on larger maps.
It’s also versatile. You could potentially scout expansion locations, or use it to determine whether the enemy has pulled his workers for an all-in. You could figure out whether an expansion is saturated to find out how much the foe has invested in economy. Though the benefits would decrease as the game drags longer.
The exploit does have a couple limitations. If all the mineral patches are being mined, for example, the path won’t change. The optimization also only works with rallied workers—if you issue a move command to mine the mineral patch, your worker decides where to mine until he’s at the patch.
Reddit user rathorse revealed the exploit, and it’s spawned quite a discussion on the Starcraft subreddit.
Blizzard community manager Randy Jordan has said that they will reveal more “soon.” But Blizzard has a long history with pathing issues in the fog of war, and they haven’t been fixed. Units will path around buildings they can’t actually see, and it’s been an issue since the game’s launch. It’s application is not as readily apparent—you can’t use it to scout an enemy’s location, for example, until you’re actually up the enemy’s ramp. But it’s a problem they’ve largely left untouched.
It’s unclear whether the exploit has been used in competitive matches. One Reddit user claims his Masters level coach used the exploit in his replays, but no one has yet found a specific instance of it in a pro match. Though some claim it explains some of the many instances of Korean pro gamers inexplicably making the correct change in strategy without proper scouting.
Whatever the case, the cat’s out of the bag now. And while Jordan says there’s no need to “explode sweet kitties,” it’s probably for the best if Blizzard nukes this exploit before it causes any real damage. Or any more damage.