Galactic Civilizations IV: Supernova Galactic Civilizations IV: Supernova Galactic Civilizations IV

GalCiv IV: Supernova Dev Journal #31 - The AI Strikes Back!

Published on Thursday, November 9, 2023 By BATTLEMODE In GalCiv IV Dev Journals

One of the most common questions I see asked in the 4X gaming communities online is “What are the 4X games with the best game AI?”, and inevitably someone will mention one of the Galactic Civilizations games in amongst some of the other greats of the genre. Usually, it’s GalCiv2, but the original PC game and Galactic Civilizations III pop up occasionally too.

With such a respectable heritage, Galactic Civilizations IV: Supernova had big boots to fill. We think the AI is pretty good now and up there with the past games in the series, but there’s always room for improvement, and one common complaint that we received shortly before launch was that the AI was behaving in an unsatisfying way when it was at war with the player.

Firstly, even if an AI-controlled civilization had built a large and powerful empire, bigger and stronger than the player it was at war with, it would occasionally just sit there, building up fleets but not reacting to the player’s moves until they’d gotten really close. The allowed the player free reign to set up coordinated attacks on enemy Core Worlds and Colonies, which the AI struggled to react to and it often looked to just be sitting there, waiting for you to kill it.

The AI in Galactic Civilizations plays fairly: that means it plays by the same rules as the player, including its vision range and ability to detect threats, and one of the consequences of this is a regular check for threats, which can be computationally expensive if not done efficiently. Optimising the AI thinking process a little too much led to it not spotting out far enough.

This issue has now been addressed, with the AI looking a lot further out to detect incoming threats, which makes the AI a much more dangerous opponent when engaged in a war. It will also better protect its homeworld in wartime.

Furthermore, it is now a lot better at figuring out if the player is a threat, meaning that it is more likely to declare war in the face of hostile behaviour.

Finally, it will now build balanced fleets, with less of the fighters and bombers it tended to field in heavy numbers, and more of the larger ships, ensuring that it’ll do better in keeping up with the player’s fleets.

Before this patch, all of the above occasionally created situations like this one from a recent game of mine, where the AI just didn’t react to my invasion fleets well enough and I easily rolled over half the galaxy by turn 153, with not a single war declaration from the AI all game.

Things have improved! In this new game, the Drengin declare an early war to take advantage of the fact I built a lot of infrastructure with no defending fleets.

And here’s a huge invasion by the Mimot Brotherhood, who are fed up of the Yor’s constant expansion and corruption of their fuzzy youngsters with a constant barrage of ear-splitting techno music.

On a non-combat related topic, the AI should now pick better colonisation targets for its colony ships, preferring the better class worlds over poorer neighbours if possible.


Galactic Civilizations IV: Supernova Dev Journals