Starcraft AI blog

I ran a 15 game match of this year’s tournament Steamhammer versus last year’s tournament Iron. This is a true year-over-year comparison. By comparing the 2017 SSCAIT Steamhammer versus the 2016 SSCAIT Iron, we can get a measure of how much Steamhammer has improved.

Over the course of 2017, Iron has consistently stayed well ahead of Steamhammer, fixing weaknesses before Steamhammer was able attack them properly. I think Iron has even pulled ahead a little, which is impressive because Iron is stronger and therefore harder to improve. Last year’s Iron versus last year’s Steamhammer goes to Iron with a few losses, this year’s Iron versus this year’s Steamhammer goes to Iron with maybe a couple losses, maybe none.

It turns out that Steamhammer has more than caught up with last year’s Iron. The score was 10-5, new Steamhammer over old Iron. Steamhammer won both with mutalisks (which Iron at the time thought it was ready for) and with lurkers (which old Iron was not prepared for). 2016 Iron was already tough, so it’s a good result. The result table here is from Steamhammer’s point of view.

The games were varied, especially considering that Iron plays a single strategy, and both sides got to show their strengths. Some were one-sided smashes for one player or the other.

Steamhammer was able to prevent too much damage from Iron’s standard 3 vulture runby with zerglings. Iron’s vulture micro at the time was not slick enough to keep the vultures safe from speedlings in the zerg base. Or to say it differently, Steamhammer’s micro has improved enough to nab the vultures when they get stuck on a building or take a wrong turn.

In a number of games, Steamhammer won by getting ahead of Iron in workers. When mutalisks fly in, Iron has turrets ready and works hard to keep them repaired. Steamhammer likes to pick off the repairing SCVs. It’s costly in mutalisks and reduces the immediate pressure, but zerg gets ahead in macro and can win later in the game.

Iron’s forward turrets protecting its vulture contain sometimes confused mutalisks and distracted them from what they should be doing, but I don’t think the effect was decisive in any game. Loss of drones that tried to exit through the vulture contain was a problem, though.

It was striking that old Iron did not scout the map in the middle game. If Steamhammer squeezed a drone past the vulture containment and the game continued long enough, zerg could set up additional bases that remained safe throughout. It happened in both of the hive tech games.

What do the last 2 days’ results mean? In the SSCAIT 2016 round robin phase, Steamhammer 0.2 finished tied for places 16-17, and the latest Steamhammer is stronger than its much-improved successor Steamhammer 1.0. Iron finished 5th with 89% win rate, and the latest Steamhammer is stronger. Steamhammer improved tremendously in 2017, so much that it would have likely have finished in the top 4 last year if we sent it backward in time. Where did I leave that time machine?

We’ll see how it does this year. The tide has risen all around. Still, 2018 had better watch out!