Starcraft AI blog

Part of my regular change list for each new version is a list of openings I’ve added, so here’s another preview. The list is long this time, but easy to write up. Only a few of these openings are configured for regular play, but all will show up now and again.

Steamhammer’s new proxy skills enable a huge range of cheese builds. I wrote 2 or 3 for each race, sort of as samples.

terran

• In base proxy openings ProxyBBS and ProxyFactory. Ecgberht occasionally pulls out a similar proxy factory, which has scored wins over Steamhammer. These builds annihilate unready opponents but show execution weaknesses if the enemy is able to defend at all. BunkerNatural makes barracks in the center and bunker at the enemy natural, and scouts at a timing so that it just barely works reliably on a 4-player map.

• 10-10-10Vultures gets vultures earlier than the standard factory timing. I wrote this to test zerg reactions to fast vultures. Might as well keep it.

protoss

• Proxy2Gate in a corner of the enemy base, which I haven’t seen another bot try, and CannonRushNatural with dragoon followup, also new to bot play.

zerg

• Burrow versions of existing openings, zergling openings with different timings. It is part of my followup on the burrow skill. As burrow gains more uses in the future, these openings should show up more often. 6PoolBurrow 6PoolSpeedBurrow 8Hatch7PoolBurrow 8Hatch7PoolBurrowB 9PoolBurrowB 9PoolSunkBurrow OverpoolBurrow Overpool_3HatchBurrow 9Hatch8PoolBurrow 10HatchBurrow Over10HatchBurrow 3HatchLingBurrow 5HatchPoolLingBurrow.

• Proxy openings: Proxy8HatchNatural makes a quick hatchery in the enemy natural and sunkens it up. AntiTyr and AntiTyrLurker are the same idea, but timed much later to counter the Tyr protoss build where it makes cannons in its base and builds up for a timing attack. AntiTyr serenely swallows the attack and wins. Steamhammer still needs a couple more skills before it can do Fried Liverpool.

• AntiFactory2 is a slightly faster version of Steamhammer’s longstanding anti-factory opening, with hydralisks first. The original opening was timed to stop a 3-vulture runby, but lately a couple of terrans have been winning with a 2-vulture runby which is earlier and sneaks in before the defenses are ready. AntiFactory2 closes the gap. I configured it as a top answer to factory openings, so it should be fairly frequent.

• 11Pool is slightly faster than 12 pool for ZvZ, filling a small gap.

• 10HatchLing and 10HatchLing2 are specialized versions of 10 hatchery 9 pool which go all-in on zerglings.

• Experimental openings: Phlegethon I timed and showed to be inferior. The alternative 2x10Hatch (10 hatchery, 10 hatchery, 9 spawning pool with repeated use of the extractor trick) I have not timed, so in my ignorance I allowed myself to write variants 2x10HatchSlow 2x10HatchAllIn and 2x10HatchBurrow. The less I know, the more fun stuff I get, there’s a lesson!

• Over10Hatch11Pool starts with the same extractor trick-overlord-hatchery sequence as a number of common Steamhammer builds, but inserts a couple extra drones before the spawning pool to build up the economy.

• Going the opposite direction, 3 hatcheries before pool but cutting drones to get the hatcheries faster than standard, are 12-11Hatch, 12-12Hatch, and 12-13Hatch. I was pleased with these and added 12-11HatchLing as a zergling all-in version.

• 2HatchLurkerPure is a variant 2 hatch lurker build which includes minimal zerglings, making drones instead, so that there’s a little more economy. I figure that if opponents lose because they are unprepared with detection, then the zerglings may not help much.

• QueenRush and GuardianRush are not really useful except for testing (the only reason I wrote the queen rush in the first place). But then, I used to think the same about the hive rush build, until it scored wins over BananaBrain. At least they’ll be entertaining if they ever show up. The queen rush makes a half dozen queens with broodling nice and early in the game.