Starcraft AI blog

The latest SSCAIT weekly broadcast included a Steamhammer-Dragon game where Steamhammer went up to five hatcheries before it started its spawning pool, a crazy risky build that loses to any early attack. Dragon did not attack early and was hammered into the ground by huge macro. Sonko, narrating the game, rightly concluded that Steamhammer’s opening was the result of learning, though the opening timing idea he mentioned is still on my to-do list. Anyway, five hatches before pool is one of Steamhammer’s favorite builds versus Dragon, but it also plays others, and not always successfully. I thought I’d briefly list a few recent games to show how tricky it can be to choose openings. Even if you know the enemy’s timings, it is still tricky.

7 hatch 6 pool speed, a zergling rush that starts slower than the pool-first rushes but hits harder because of the two hatcheries and the zergling speed research. The opening leaves only 7 drones to power the two hatchery production, so it’s very much all-in. Dragon saw it coming and reacted with a bunker in its main, though for some reason it followed with an expansion CC which it lost without canceling. Even so, Dragon’s defense was better than Steamhammer’s attack, the all-in failed after vultures arrived, and Dragon was in a winning position. But (no doubt due to some bug) terran left only 1 SCV on gas and suffered a severe vespene shortage, and compensated by going mass vultures, not a strong backbone unit for a terran army. The game turned much more exciting than it should have been.

9 pool into 2 hatcheries, with early but not heavy pressure. Again Dragon made a bunker in main and defended easily. Steamhammer droned up well, keeping pace with the terran economy, but could not also make a strong army. Zerg ran into trouble.

5 hatch before pool, like the broadcast game, except this time Dragon got a vulture into the zerg base before defense was quite ready, then followed up with wraiths when defense was not even close to ready. Zerg struggled but finally stabilized, and the game was on. This is the most interesting of the games.

The first two games are fast rushes. One was all-in and the rush failed, but the opponent’s game plan was discomposed by an unforeseeable factor. The other was not all-in and looked successful at first, but did not actually keep up. Even if you recognize the enemy’s tech and attack timings, it’s tricky to choose an opening that exploits them successfully. Starcraft is complicated! The third game is a reminder that the enemy gets a vote, and can change up its timings, or can play its builds sloppily so that the timings vary. At a minimum, you have to take into account the range of timings.