Why Great Strategy Games Need Great AI Generals

Good game AI is notoriously tough, but a capable computer opponent can create magic.
July 16, 2018, 2:30pm
'Rise of Nations' screenshot courtesy of Microsoft Studios

When I was a kid, my friend and I used to play Command & Conquer: Red Alert together almost every other night over a dial-up connection. Mostly, we played against AI opponents, trying to take on more and more of them as we got better at the game. The catch was that the AI was incredibly passive: Save for a few small raids, AI players would happily build ever-larger bases and armies to no apparent end. However, the moment one of your units attacked their harvester, the AI would attack relentlessly with everything it had. It was incredible to watch happen on the minimap: In the blink of an eye, the entire map would seem to lurch toward whichever player had committed the offense. It was basically the They Are Billions of the 1990s.

Advertisement

Once you realized the AI had such hard-coded responses, it was easy enough to manipulate and defeat. But I think I’ve always looked for games that could bring back that moment when my friend and I would watch the tide of enemy troops roll in, exchanging a few last messages about our battle plans before we were fully committed to our plan.

Lately I’ve been playing a lot more classic multiplayer RTS games. The likes Age of Mythology and a lot of Rise of Nations, plus some more modern gems like Homeworld: Deserts of Kharak. But it’s striking how few games have truly great AI opponents who can play a full game. The more you play of these games, the more you realized that RTS skirmish AI is usually some version of that single-minded Red Alert AI: It knows a couple tricks, it has a couple things it will prioritize at all costs, but it doesn’t really have any way to interpret context. One AI might teach you about surviving rushes, another might teach you about bringing down a turtled-up economic giant, but very few can actually handle all the scenarios that occur in a long RTS session. They can still be a lot of fun to play against, but after a point you’re playing against the specific quirks of the AI and not really learning the game as a whole.

'Age of Mythology' screenshot courtesy of Microsoft Studios

But then there’s Rise of Nations, whose skirmish AI has gotten me to fall back in love with that game in a big way. While it’ll still commit some ghastly errors at times—like trying to run a heavy naval blockade with a herd of single-file troops transports—it’s one of the few AI opponents I’ve faced that actually feels like it is playing the same game that I am, and not just relying on a few prescribed tricks.

Most importantly, this is an AI that is capable of mounting an honest-to-God comeback if you’re not careful and get overextended. Last weekend I started testing myself against tougher AIs and my games started to fall into a very fun, slightly excruciating pattern. The game would be neck-and-neck in the opening phases, but I’d eventually be in a position to start making a push. At first, AI armies would fall before me, and so would a few of its cities. But then I’d start running out of steam, and things would fall into a bitter stalemate. Yet time and again, this would end up favoring my AI opponent because it would simply out-manage me while I fixated on controlling my army and keeping a tenuous hold on my hard-won gains. Suddenly I’d notice more advanced enemy units taking the field, then there’d be more of them, and then my entire empire would start to buckle under the weight of wasted resources and the unceasing advance of my now-superior enemy.

'Rise of Nations' screenshot courtesy of Microsoft Studios

Admittedly, I was all kinds of rusty at Rise of Nations (a game that buries you under nuanced decisions and trade-offs), and I was still coming to grips with both the game and the AI. But that’s the amazing thing about Rise of Nations skirmishes: They actually force me to learn the whole game in order to win them, not just a few patterns. If I take let down my guard for even a second, no matter how long the game has gone on, the AI will try and find a way back in. In one memorable case, that meant shelling me with nuclear weapons while my late-game army bulldozed across the map, racing to win the war on behalf of a homeland that was fast-becoming a wasteland. They didn’t.

What have been your favorite AI adversaries? What computer-controlled enemies have made you feel like you’re battling another mind, and not the equivalent of a pitching machine in a batting cage? Why?

Let me know in today’s open thread!