Starcraft AI blog

Check out this event in the game webgames vs Steamhammer on Sylphid from SCHNAIL.

Human players of terran and protoss normally group their production buildings. It’s pretty much a requirement for efficient macro. It also introduces a vulnerability: If the opponent maintains control over the area of your production and you don’t already have enough army to force them away, then you are in deep trouble. Any new units you produce will die, so you cannot regain control of your production. Here, terran has built turrets to protect its main and natural mineral lines, but none next to the barracks, an oversight that invites attack.

In the picture, I judge that Steamhammer does not hold enough control over the terran barracks to win, even though the selected barracks is in the red and in danger of burning down. It did hold that much control earlier and had strong winning chances, but frittered it all away: Mutas attacked the barracks, then were distracted away, then attacked the barracks again, then were distracted, and so on, losing mutalisks and allowing the marine count to build up. Bots rarely group their production buildings, so I never taught Steamhammer about the leverage of controlling the enemy production. In the picture, the mutas are about to be distracted away for the last time. Terran repaired the burning barracks, had unhampered production, and won easily with their huge economic advantage.

Distractibility is an issue in itself. I need to improve tactical target selection so that it doesn’t change its mind so frivolously. The skill of controlling the enemy production is a harder question for me, from a development point of view. The skill would be just as valuable in bot-vs-bot games when it applied, but it would not apply often. I wouldn’t be tuning specifically against human play, but it leans that way.

There are specific anti-human skills that don’t help against bot opponents. Humans often try to overwhelm the opponent’s multitasking with threats and feints and multi-point attacks. Multi-point attacks in themselves call for multitasking ability. Bots can do the same much better. I don’t have any plans to tune to exploit human weakness in multitasking, though I suppose I may come around to it in the distant future.