Starcraft AI blog

I’m pleased with how the new Steamhammer 2.3 is doing. Not only is it scoring wins where it could not before, its play looks sharper and cleaner. It’s mostly due to bug fixes. It beats XIMP by Tomas Vajda again (command jam bug fixed in 2.2), and it is back to its former success with heavy early zergling pressure (unit movement fixes in 2.2 and 2.3 plus zergling value fix in 2.3). I added many new openings in 2.2, and the unsound “dawn hydra rush” (those hydras arrive in the morning gray) is scoring well against SAIDA due to SAIDA’s broken reaction. The same opening worked against Iron when I wrote it, but one of Iron’s updates added a reaction and Iron is now safe. The value of the other new openings, positive or negative, will take time to show.

Randomhammer’s better building placement make bases look prettier. Having fewer buildings bursting into the center of the map can only help play, though I think that most opponents which are able to exploit the vulnerable buildings were going to win anyway. The tank improvements make terran factory play look almost... non-ridiculous. The tank play was awesomely bad before; now it gives the impression of trying to do something sensible, though it doesn’t always succeed. And, of course, drop openings work again; that may not be reflected in performance right away, because Randomhammer remembers the results of its previous version, which learned to avoid the broken drops against some opponents. Still, I’ve seen a few crushing drop games.

BASIL is better than SSCAIT for strength measurements. Here is Steamhammer’s elo graph from BASIL:

Version 2.3 was uploaded 2 April, and includes the improvements in 2.2 and 2.3, since the previous running version was 2.1.4. The graph shows a strong rise on 3 April, 75 elo over its base, with a peak nearly 50 elo higher than the next highest peak in the graph. It’s pretty good evidence that Steamhammer is improved; the elo increase is likely 50 or more.

The same for Randomhammer:

This is not as clear. The peak begins to rise on 4 April; I think that is mostly because of game scheduling. It is about as high as previous peaks on the graph, and it is not convincing that it is statistically meaningful rather than a random winning streak. I’d say there is weak evidence for a strength increase. I will be disappointed if Randomhammer doesn’t end up showing a detectable elo rise.

I did a round of work on overlord safety last fall, and improved it enough that it was no longer one of the top weaknesses. Now other aspects of play have improved enough that overlord safety is again a critical weakness. There are also 2 game-over bugs that guarantee a loss. One causes drones to hang out with the minerals instead of mining; it’s rare. The other causes general confused behavior, and it is extremely rare. Rare bugs with no identifiable trigger condition are tough, but they have to go.