“AI only needs to be as good as the character’s life expectancy.”
That’s the rule of thumb for the AI programming world. Or at least that’s what we are all taught. In theory, it’s a sound rule. If the average enemy is on screen for seven seconds, make seven seconds worth of behaviors. If they are going to be observable for five minutes, a seven second loop of behavior is going to get old really quick. A recurring character in an RPG may have a good amount of face time broken up over the course of the game, but that is still in reasonable chunks (and generally entirely scripted). But what if the AI agent is going to be around all the bloody time? I mean not just hanging out in the background like a vendor or a citizen in Neverwinter Nights… but around around — like an “in your face” around. A “glued to you at all times” style of around. Now THAT is a lot of AI! And yet that is what is happening in the game world today.
Early on, the pull of “one against the world” games was strong. What could be cooler than being a single prisoner in a Nazi castle that just overpowered his jailer… and now has to fight his way out through half the bloody German army? (For those of you old enough to remember the original Escape From Castle Wolfenstein in 1981, how much did it panic you every time you heard that scratchy, distorted yell of “SS!” coming out of your Apple ][ speakers?) This formula was made even more prominent by the arrival of the “Doom effect”. One marine against all of Hell? No big deal. A single scientist against hundreds of aliens? He can handle it.
Well, apparently the game industry got tired of the clichéd asymmetry. There has been, of late, a new thrust towards what is being generally termed “sidekick AI”. We saw it with Alyx in Half-Life 2, the Arbiter in Halo 3, the (much-maligned) “PAI” in Army of Two. We will see even more of it with the now mythical (yet strangely unnamed) “dog” in Fable 2 that Peter Molyneux claims will bring us to laughter, love and tears and make us abandon all desire to ever get a real pooch because this one adores us with all his precious little canine heart and we will bond forever until such time as he gets his happy little head chopped off in a horrific battle, inspiring us to fly into a berserker-like rage of vengeance against all evildoers who would senselessly harm little doggies… *ahem* Sorry. I’ve been listening to too many Molyneux interviews.
Video 1: A demo of the dog AI and behavior in Fable 2. This is the first of 3 videos at GameTrailers.com. They are from GDC 2007 so they are somewhate dated — but impressive nonetheless. You can find all three videos here.
On the other hand, isn’t that what needs to happen? If we are going to have an AI that’s tagging along behind us for hours on end, wouldn’t it be better for us to love him/her/it? Let’s face it, if you are playing 10 or 20 hours of game content, any form of repetitive AI may have you digging through the manual for scouring cheat codes online in order to find the “slap your sidekick upside the head” control. You can’t simply get away with seven seconds… or even 5 minutes of believable behavior. Beyond that, the sidekick needs to be more than just something you are entertained and amused by. You need to be able to depend on it… as if it were your lifelong partner.
The Power of Two
Trusty sidekicks have been a staple in all types of adventures in literature, movies, and TV. The Lone Ranger could never have heard enemies coming if Tonto hadn’t been there to put his ear to the ground. Agent 99 kept Maxwell Smart in line just like Penny did for her goofy uncle, Inspector Gadget. The Brain had Pinky (for what that’s worth) in his quest on world domination. Shaggy would have had to eat all the munchies if Scooby Doo hadn’t been there to help out. (I’m not sure how relevant this is to my topic – I just couldn’t leave them out, though.) (Oh… and don’t get me started on Scrappy Doo.) And Alex, the intrepid AIGameDev hero, would have to write one more column each week on top of crunch time at his contract if it weren’t for the stalwart and ruggedly handsome (in a 40ish, mildly out-of-shape, computer nerd sort of way), Dave.
On the other end of the scale is James Bond. Let’s face it… Bond was cool. But Bond’s sidekicks, usually some hottie-du-jour (a concept which the game industry did seem to get a handle on), were usually less than stellar from a mission-functional standpoint. (And I am, indeed, limiting the scope of the analysis to mission-functionality.) Often times, Bond spent a good deal of time pulling the woman’s proverbial bacon out of the fire. (That’s about as safe a metaphor as I could insert there.) And, unless you are playing Super Mario Brothers, endlessly saving ditsy damsels who can’t keep from getting into trouble isn’t a game design staple. If you want a mission partner who can be less distraction and more asset (regardless of her distracting assets), she’s going to need to show some smarts.
Perhaps the duo that best models the way game sidekicks are today, however, is Batman and Robin. Batman looked cool, sounded cool, had all the nifty toys stashed about his person, and did most of the heavy lifting when it came to whooping buttocks. Robin knew his roll well. He did a respectable job of whacking around the non-critical bad guys, gave Batman someone to commiserate with when they were in trouble, sometimes came in handy in peculiar situations, but otherwise was relegated to providing a wearisome (and often abstractly theological) commentary on the events of the moment. In fact, Robin tended to provide most of the chatter yet strangely left all the decisions up the relatively taciturn Batman.
Compare that to how games tend to run. You have some annoying, mildly useful person circling you like a small moon, kinda holding his own in a fight – maybe enough to allow you to step back and toss down a sports drink, but whose true calling seems to be making repetitive and vaguely helpful comments that, at times, cause you to pause for a moment and ask “what the heck did he say that for?”
Invulnerable or Expendable?
Even the above illustration is better than some of the options you see in the “squad-based” shooters these days. Often, your teammates are one of two varieties. Tapping into another TV/Movie reference, if you were to make an aggregate of every Star Trek “Away Team” that Kirk took with him, you will realize that there are those that always live and those than always die. No matter what befell the team, you could count on the fact that Spock, McCoy, Bones, Sulu and Chekov were going to come out the other side. After all, they are necessary for the plot… not just in this episode, but in all future episodes as well. On the other hand, if you were one of the unlucky chaps who wore a red shirt, you were toast. You were specifically included on an away team just to run in front of the camera and die in spectacular fashion. It wouldn’t be fair if Kirk’s entire team was always completely unscathed, right?
Photo 1: Star Trek Red Shirts have become an accepted metaphor for “someone who is about to die”. How many teammates in shooter games fit into that category? And how many show the uncanny invincibility of Spock, Bones, etc.?
It didn’t take me long playing Call of Duty 2 to realize that there were some guys who were going to last throughout the whole theater campaign and others who were there specifically to die in front of me in some magnificent script-and-trigger festival. At least they weren’t denied all dignity; they were all given names so that I could take a moment to mourn their passing. If I spent 15 seconds pondering the life of Pvt. ??????? ??????? (btw, that’s “Red Shirt” in Russian), then his memorial probably lasted as long as his on-screen life. Was this marked difference in longevity based on the fact that my partners in perpetuity were smarter than their firearm fodder brethren? Nope. They were often just as dumb. They could have taken a proctologic potato masher and still been smiling away as if we were about to sit down for a pleasant tea-time. And with that asinine smile (so to speak), my ever-tenuous suspension of disbelief was out the window. They didn’t survive because they did something cool and pseudo-heroic (in a Robin sort of way), they survived because they were allowed to defy both probability and physics (in an Inspector Gadget sort of way) in order to do so.
So, Dr. Frankenstein, How Do We Create This Sidekick?
So, the challenge is laid before us. Since many of us can’t always play with real friends at our sides, we want our synthetic gaming partners. We want them to be engaging so that they are not completely dull — but we don’t want them to be nattering idiots that we may want to shove into the nearest lava pit. We want them to be competent fighters, not only as individuals but as a cooperative part of our little team — but it would look stupid if they were blatantly invincible. We want to care about them… to be attached to them… to want to protect them — but don’t want to be reminded that, even if we don’t protect them, they will still be around in the final battle because they are necessary for the plot. There’s a bit difference between wanting a relationship to continue and knowing that it is fore-ordained to continue whether we care or not.
That’s a lot of splitting the difference. It would seem that we have to hit 3 or 4 different “sweet spots” — and all of them are in areas that are already daunting tasks for game AI. So we need to ask ourselves some questions. Is this something that is even doable? If not, let’s just give up. But, running with the premise that we can accomplish these lofty goals to at least some extent, where do we begin? What is the biggest challenge in creating that magic blend that we can actually stand to plod through days and weeks of gaming with this sidekick tagging along? And is there even agreement on what that magic blend is? I’m sure there will be plenty of argument on this point as well. But from an AI standpoint, is it even technically feasible?
To paraphrase the titular sidekick…
“Holy design problems, Batman!”