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Comment by skybrian | Hacker News Reader

There is a genuine advance here, but keep in mind that when an AI is developed by the game developers, they're not necessarily playing to win, but to make the AI fun to beat, and without using too much computer power, which would make the game slower. Also, due to commercial pressures it's tough to put a lot of effort into the AI for a game that's still being changed to make it more fun.

Even now, I wouldn't really expect to see most game developers start using the latest machine learning techniques to build their own AI's. Maybe the really successful games with competitive leagues might be interested?

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Hi Brian,

I really hope this will change, though. Skilled AIs could make so many games more interesting and better.

Many online games really suffer from bad multiplayer experiences. Players that drop in the middle of a game, ...

If Overwatch, Destiny, ... had really good AIs, that would make the game more attractive. If a player drops, they could replace it with similarly skilled AI. Instead of waiting for 12 players of the same skill-level, they could just play with some AIs.

They could even make it such, that humans win 70% of the time, and let the AIs just lose more often.

Yep, I'd like to see it too. If one popular game really did single-player with AI opponents well, maybe it would start a trend?

AI development probably needs to be made easier, somehow. Game developers have a lot to do.

>There is a genuine advance here, but keep in mind that when an AI is developed by the game developers, they're not necessarily playing to win, but to make the AI fun to beat, and without using too much computer power, which would make the game slower.

This point is being brought up a lot, but I don't really buy it. Yes, there have been instances where the AI being too good discouraged players from playing the game as much, but this almost always happens due to the AI having some inhuman advantage that a person could not really replicate. I think players do want the AI to pose a challenge - that's what a lot of casual PvP games are about. Humans are (were?) the only ones that could offer a fair match against another human.

I will absolutely grant you the computational power point though. However, as hardware advances, this cost will become more and more acceptable.

I don't expect to see widedspread adoption of this in commercial games within a decade, but I think that in 2 or 3 decades this will be the norm. In fact, I would bet that once we can make an AI that is good at a game, we can also make it weaker. A game could estimate a player's skill rating silently and then adjust the AI's strength to give the player a difficult/fun time.

Of course, it could just be that AlphaStar is able to play well against humans, because players treat it like a human. Maybe the AI still has standard game AI-like weaknesses that can be exploited if people know that they're playing against an AI. Eg some Diamond league player went mass ravens and kicked AlphaStar's ass. The AI would have to learn how to deal with stuff like this on the fly and I don't think we're there yet.

Well, yes, you need to ramp up the difficulty in a way that's fun.

The article describes "exploiter agents that focus on helping the main agent grow stronger" as key to their approach. That seems promising? Maybe it could be used to make bosses with specific strengths and weaknesses where part of the game is figuring out how to beat them.

I think part of the problem is that every videogame is a parlor trick in a sense. Unless you are a tournament player or someone who enjoys a really hard challenge, the bulk of the customers who buy the game just want to enjoy the illusion of a challenge. You don't really need a complex AI directing the hordes of enemies you want to defeat; you just want the illusion of battling enemies and emerging the victor, and how the game accomplishes this is not that relevant... unless the trick is so blatant that it breaks the suspension of disbelief, of course.

Why does this matter? Because the trick is often less effort than the real deal. The point of videogames is to entertain you, and the goal of game publishers is to turn a profit while doing so. Obviously there are some exceptions, and indie/free games might have different goals (we all know indie games that can be punishing, like Dwarf Fortress).

I remember with the original Left 4 Dead by Valve, they claimed there was an "AI Director" that modified the map according to how well you were doing, "adapting" to how you were playing. In practice it amounted to closing some sections of the map according to how easy you were killing zombies without dying. So this wasn't really AI but a glorified IF-THEN-ELSE trick, but what does it matter? It served its purpose. Do we really need something more complex (and expensive!) when killing zombies in L4D?

To extend your point, it is also clear from analytics in Steam & mobile gaming that games have massive amounts of player dropout. It is pretty rare, even in relatively short single player campaigns, to see 30% of people who bought the game finish it. So effort making the AI even better is always going to only be for an extremely small niche of players that play a game long enough to exhaust the limits of simple AI.

Just look at the achievements for Left for Dead. Only 40% of all players have got the achievement for "kill one of each Uncommon type" which is trivial to get if you play for a few hours.

Steam numbers are massively inflated by the tons of game purchases that come through sales, bundles, and giveaways and are never played. I have something like 600 games in my Steam library, and I would bet that the median playtime would be 0.0 hours...

Just today I saw something that looked interesting, and it was 85% off because of a Halloween sale. So I grabbed it for a couple bucks. Free time being such a rare commodity, there's a solid chance I never even install it... and then there's always Stellaris or Mount & Blade or Medieval Total War that I could happily play until the heat death of the universe, competing for my attention.

Isn't that just proving my point?

Most people who buy your game aren't going to invest even 10 hours in it or come close to maxing out the AI because they only picked it up because it was 85% off during a Steam sale.

Maybe you'll be able to figure out from Early Access numbers how popular your game is and whether you need to invest in super-awesome AI. But it seems like for most games it would be a waste of effort. More likely it would be retrofitted into an already popular game in a DLC or future patch or something.

>Maybe you'll be able to figure out from Early Access numbers how popular your game is and whether you need to invest in super-awesome AI. But it seems like for most games it would be a waste of effort.

Maybe the reason people quit your game is because of the AI. What made me stop playing Heroes of Might and Magic 6, Civilization 6, and Total War Three Kingdoms is the poor AI. It takes the fun out of the game, because at lower difficulties the AI puts up no challenge and at higher difficulties you're just exploiting the AI the same way over and over again to keep up.

You might think that that's fine, because you already got the money, but then you'd be looking at it from the perspective of singular games. But studios usually don't just release one game and then disappear. After my experience with HoMM 6, I had zero interest in HoMM 7. 2K Games could release Civilization 7 tomorrow, but without them showing that the game's AI is much better than in civ6, I probably wouldn't pick it up. Yes, the Civilization series will still have players, but it could easily just fizzle out like many other franchises and even genres.

You also can't add this in as a DLC, because people make up their mind about a game near the start. This only works if the game already has longevity, but at that point the game is already popular, so does a better AI at that point make a difference?

It doesn't matter how short or long the singleplayer campaign is. AI in games is so simple and rudimentary that you'll have it figured out in most games in less than an hour. You might not figure out the most effective ways to exploit it, but usually you'll figure out something. This alone can make the experience boring, especially when your game is heavily focused on playing against the AI.

While there are certainly plenty of parlor tricks and other illusions, I think in the best case, a game can contain a finely tuned learning experience, where by training you actually do get better at something. (Often something unimportant, but still fun.)

Throwing people into the deep end of the pool usually doesn't work so well. Scaling down the difficulty helps, but really what you want is challenges that teach you something. And you don't really need AI for that.

Last year I started learning to play accordion out of a method book. It has a bunch of songs ordered from easy to hard, and they're also chosen to teach certain skills. It reminded me quite a bit of good level design.

I agree with everything you said :)

>You don't really need a complex AI directing the hordes of enemies you want to defeat; you just want the illusion of battling enemies and emerging the victor, and how the game accomplishes this is not that relevant...

Yes, and the current game AIs are completely and utterly incompetent at it. AI in video games only provides a challenge when the mechanics of the game are challenging or the AI is cheating.

>Do we really need something more complex (and expensive!) when killing zombies in L4D?

Not in L4D, because you don't play the game to kill zombies. You play the game to play with other people. If L4D didn't have coop then the game would likely not have gained popularity.

You're right that players want a challenge that they can overcome, but current AI in video games does not offer that. The AI always ends up being so weak that play against the AI cannot be the focus of the game. The focus has to be in mechanical play, puzzles, story, atmosphere, multiplayer or something else. The only way AI keeps up is with inhuman mechanical play or cheating. Neither feels fun to play against, because the counter to it is to figure out how to exploit the AI, after which the game becomes more or less trivial.

> Yes, and the current game AIs are completely and utterly incompetent at it. AI in video games only provides a challenge when the mechanics of the game are challenging or the AI is cheating.

I wouldn't say "incompetent", but yes, the mechanics of the game must be challenging and/or (often) the AI must cheat. I'm saying this is enough most of the time; there's really no incentive to build a better AI for videogames because (my hypothesis) most gamers don't care. The illusion of challenge is enough, most of the time. The goal of videogames is to entertain, not to really challenge (again, with the exception of tournaments and competitive gamers, who are a niche within a niche).

You mentioned Heroes of Might & Magic in another comment. I played the heck out of HoMM2, some of (I think) HoMM3 and got bored with the rest. But I wasn't bored with the AI; I got bored because it was the same formula again and again. The genre itself soon felt like a tired formula. Note that the "AI" -- cheating or not -- of HoMM felt horribly difficult to me. I lost battles more often than I won; the only trick that reliably worked was to start the fight with a lot more troops than the computer enemy, and that's not much of a trick! Not a lot of places to learn effective tactics back then either, maybe the hellpit that was GameFAQs?

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