Dear AI…

Brad Wardell understands that ultimately, a strategy game is only as fun as the opponent you’re playing against. So a good AI is of paramount importance to a strategy game, particularly a single-player only game like GalCiv2. I also have an unhealthy interest for AI behavior and a good AI can make me ignore many shortcomings in a game – just like a poor AI is very hard to compensate for in my eyes.

I’ve said much about the GalCiv2 AI in the past, but with Dark Avatar, there are still points worth noting. Let me start by saying that the expansion, overall, improves the AI. For example, it uses espionage and responds to your spies competently, and it also runs its economy better. Of course, the effects of the CPU slider are fairly noteworthy.

Taking a look at the different difficulty levels, maybe some shifting or an extra level is in order. The Normal difficulty (on which I played one game by accident) is a complete cake walk. You can win on Normal without having a real understanding of the GalCiv2 economic system, without specializing planets and without even being able to maintain your spending at 100%. The next difficulty level, Challenging, is a relatively steep increase – the AI starts behaving aggressively if it has good military capacity, and the level can actually present a challenge if you’re hated in the galaxy. The increase in difficulty between Challenging and Tough is actually less dramatic, although Tough finally requires you to do some things right (like the aforementioned specialization or 100% spending).

Now, please excuse me in advance for focusing on the AI’s weak points. There’s not much use in praising the AI and what it does well, while focusing on the negatives can, hopefully, provide useful feedback for future improvement.

As previously mentioned, Spore ships are one of the AI weaknesses. The AI is pretty shy about using these ships, and it certainly doesn’t assign a very high interception priority to incoming Spore ships if you’re trying a Korath Spore rush. Spore ships are a bigger threat than Transports, and should be treated accordingly.

The worst of AI I’ve seen in Dark Avatar relates to peace negotiations, however. That happened in my last game before finishing this review, and it’s a noteworthy point.

The galaxy was pretty evenly split between myself and the Korath, two remaining superpowers, after I had just annihilated the Altarians, while the Korath took out the Drengin. I was superior economically and in influence, but the Korath decided to attack me after not too long. The original decision made sense – their military rating exceeded mine, and the vast majority of my ships were far from the most powerful designs I could put together (I didn’t really need that much power to run over the Altarians previously).

I concentrated on military spending, also building better ships than I had before. The differences in how the AI and humans build and utilize ships are great. All Korath worlds were defended, many with several defenders. Most of my planets were either undefended or defended with some long-obsolete lone fighters. Almost all of my military ships were actively involved in the war, fighting on the front lines, while many Korath ships were staying back as defenders. Korath ships also had more power than mine one-on-one, due to their decision not to build engines (this game also had an event increasing all ship speeds). My logistics ability was better, though. Overall, the Korath military rating exceeded mine considerably.

Still, the war went well for me, and I started taking Korath planets one after another. After taking several systems from them without losing a single planet in the process, I went to see if the Korath would sign peace. They wouldn’t! By now, I was considerably ahead in technology, economy and population with my treasury probably being around ten times theirs. However, their military rating was still well better than mine, not that it was doing them any good. Some five more planets exchanged hands, and the Korath would still only sign peace if I gave them lots of technology, despite their losses.

Military rating seems to take the amount of ships into account more than their quality, and the AI trusts military rating way too much when deciding whether it’s losing a war. I think there are two sets of factors the AI should instead use. When war is declared, the AI should remember its absolute ratings numbers at that moment. Likewise, it should also remember its ratings (I mean a wide array of stats, including total production, population, etc.) relative to the civ it goes to war with. These two sets of data would provide a much more accurate indication of how well the AI is doing. If it goes, say, from a 1:1 ratio in population and economy to a 1:2 population and 1:3 economy ratio, then the war is most definitely not going well.

Ah, but the Korath unwillingness to sign peace wasn’t the end of it. The United Planets met during the war, and the issue at hand was whether to resolve all current wars. I voted Yes, which did it, with my influence being about 70%. Okay. I just didn’t want to bother with the Korath and instead went to research the Tech Victory, which wasn’t too far away for me by then. But no, the Korath declare war on me again not long afterwards, thanks to their military rating still being better, crazy as it may be. This shows that the AI also, apparently, doesn’t have memory about how it did in previous wars. You’d think that losing multiple star systems while not gaining a single planet would be enough to deter the Korath from declaring again, but it wasn’t.

Needless to say, this is an area of AI where I hope to see much improvement in the future. Ships are not the reason wars are fought. Wars are fought to gain planets or at least an economic advantage over your enemy – ships are a means to an end, and having ships while losing everything else is not a good sign.

I also found the AI ship designs not varied enough in Dark Avatar. It definitely prefers no-engine heavy pounders now, but I haven’t seen any fast, lighter-armed AI ships that would be good at outrunning heavy and slow fleets and hitting targets such as starbases or mining bases deep within enemy territory.

I’ve witnessed the AI attack with Transports. They had Transports with weaponry and were sending them to my undefended planets. As I rushed a defensive ship on the planet, the AI promptly arrived and attacked with the Transport. Given how these ships only have one hit point that just cannot be a good decision.

You can fully expect further discussion on the AI to occur in our GalCiv2 forums. I’ll end for now to prevent this article from growing to a truly galactic size.