Starcraft AI blog

The first upload of RedRum was identical in play to Steamhammer 2.3 playing terran. Since then it has been updated with changes, so I took a second look. Curiously, though the bot’s idea of its own name has been updated from SteamRoll to RedRum, it still gives its version as 0.1.

The RedRum version uploaded on 4 May had complete map information mistakenly turned on. SSCAIT software did not notice, but stream watchers noticed quickly because a debug option to draw enemy unit locations was turned on. Nobody who was actively trying to cheat would turn on both options at the same time, so it truly was a mistake. Still, it makes me wonder whether any other SSCAIT bots have complete map information turned on, whatever the reason. A corrected version of RedRum was uploaded the next day, on 5 May (the complete map information setting was the only difference between the uploads). Has SSCAIT fixed their side of the error yet? [Fixed on 11 May.] The tournament manager can and should flag that setting.

Compared to Steamhammer, RedRum makes no important changes to the configuration file—it sets bot info like the name and it sets different debug options. The opening book is unchanged. RedRum’s DLL file is microscopically shorter than Steamhammer’s, 512 bytes or about 0.05%. I speculate that it may delete a small amount of code that terran does not need (there is plenty more). It’s unlikely that it deleted a lot of code and also added a lot; we’d probably see a bigger size difference.

I played a few test games to see if I could spot changes. I set Steamhammer and RedRum to play identical terran openings, to help small differences stand out. I noticed that RedRum always claims that its opening is “enemy specific”, though I set it myself and it was not. I thought there might be a difference in the SCV scout’s behavior when it reached the enemy base. And attack/retreat decisions seemed a little sharper; maybe that has been improved. Other than that I could not spot any difference. But then, I know from experience that play differences are quite hard to find by eye. I could have misinterpreted game events as skill differences, and I could easily have overlooked other differences in play.

Still, RedRum remains very similar to Steamhammer terran. In the first test game, the initial vultures met in the center of the map and fired on each other simultaneously, and the build orders remained identical until deep into the game. That’s natural, of course; it takes time to make substantial changes.

It’s good that we’re getting at least some new bots. I have the idea that Ayran Olckers, author of RedRum, is still at the exploring stage, trying to get a firm grip on things. Bigger changes may be coming—the 0.1 version number at least says so.