Starcraft AI blog

Why do so few zerg bots make scourge?

A pair of scourge costing 25/75 can kill a wraith or corsair costing 150/100, or even a valkyrie costing 250/125, such a favorable ratio that zerg can afford to lose some scourge along the way. If the enemy flees then the scourge may kill nothing, but to send the enemy running is a victory in itself. If you have a spire, then scourge is a cost-effective part of your air defense and reduces the need for hydralisks or spore colonies to protect overlords and mineral lines. Scourge moves fast, good for scouting, and scourge can intercept drops. Scourge is gas heavy, but zerg usually has more bases and therefore more gas. When facing air units, it is almost always a good idea to have some scourge.

Steamhammer is not skilled with scourge. It maneuvers poorly, failing to attack when it could or losing scourge unnecessarily. It attacks poorly, sending too many to one target and not enough to another. And it doesn’t know the first thing about coordinating scourge with other units. But its opponents are also weak at defending against scourge, and overall I believe that Steamhammer’s scourge is more than worth the cost. In tonight’s game versus Tyr by Simon Prins, Steamhammer scourged science vessels one after another, butting heads with the terran army and holding even—until finally one vessel lived long enough to get an irradiate off, creating an opening for terran to break out. Despite some losses, scourge more than earned its pay, and greater scourge skills might have saved the game.

When I play Steamhammer versions against each other, the fight often comes down to which side lands more scourge hits. Steamhammer does not know that in a muta-scourge versus muta-scourge battle, you commonly want to hit each enemy muta with 1 scourge to leave it too weak to fight on, rather than 2 scourge to kill it (wasting most of the explosive power of the second scourge). If I taught it that....

A zerg with razor-sharp scourge skills would be a terror of the air.