Starcraft AI blog

AIIDE submission closes after today. Some bots may yet withdraw at the last moment or otherwise disappear, but we pretty much know the roster. I want to look ahead with the information we have.

race distribution

This year we have a zerg plurality. That happens to be good for Steamhammer, because ZvZ is Steamhammer’s best matchup.

The percentages add up to 98% instead of 100% due to rounding.

BWAPI versions

I was surprised how many bots were already on BWAPI 4.2.0.

The 2 bots listed as withdrawn were also on BWAPI 4.2.0. Does anybody know if or when SSCAIT will support the newer version? I know resources are limited, so I won’t be surprised if it takes time.

6 of the 9 bots still on BWAPI 3.7.4 are the legacy bots carried over from last year. Only 3 are active entrants. Surprisingly, one of the 3 is ForceBot, which seems to be a recent bot since it only recently appeared on SSCAIT and suffered some teething troubles there.

the newcomers

There are unusually many absolute newcomers, bots whose names or authors I don’t recognize. History says that most newcomers will do poorly; it takes a long time to turn an empty repository into a contender. But there are exceptions. This year PurpleWave reached #3 in CIG 2017. Last year Bereaver was a sensation. It will be a surprise if an unknown wins—but surprises happen.

• bonjwAI
• CherryPi
• cpac
• DeepTerran
• HOLD
• Inspir
• Myscbot
• Sling

I think many are especially looking forward to the Facebook entry CherryPi by old hand Gabriel Synnaeve. I’ve read the papers, and my hopes are not high. My impression is that the project is not far along. I expect CherryPi to finish in the lower half, and I mainly hope that it will show some interesting behaviors along the way.

the unpredictable

A few bots are both potential top finishers and potential also-rans. Arrakhammer and McRave have shown inconsistent results, strong play when in their best form but many losses when problems creep into the codebase. AILien was often impressive on SSCAIT, but stopped playing there after updating to BWAPI 4.2.0. I don’t know what updates it may have seen since.

the known contenders

Iron is of course the favorite. In CIG, Iron suffered because it was unready for the new and troublesome maps. In AIIDE, the maps are standard and are the same as last year. I see a strong chance that Iron will pull in well ahead.

Bots that are likely to finish high are LetaBot, Microwave, PurpleWave, Steamhammer, UAlbertaBot, and ZZZKBot. ZZZKBot won CIG 2017 and is a perpetual contender. This tournament has more new bots than CIG, which favors ZZZKBot’s exceptionally well-implemented 4 pool—it smashes opponents which are not perfectly prepared. ZZZKBot is my pick as the most likely #2 finisher. Beyond that, it gets harder for me to forecast.

Steamhammer I think is likely to finish fairly high, but outside the top 3. It will lose almost all games versus Iron and PurpleWave, and some versus UAlbertaBot (which I expect to be stronger with the new SparCraft). Without opponent modeling and unable to adjust its strategy mixes, Steamhammer is also at risk of losing many games to newcomer bots. I see the opponent model as a necessary feature for a tournament, because unknown opponents might do anything, and known opponents might have surprises in hand.

But really, we don’t know. The tournament exists to find out.

Update: The roster page now says that 4 of the newcomer bots, plus AILien, either withdrew or did not submit. 27 contenders remain.

Update 2: Now AILien is listed as submitted after all. Whew.