In a game like chess, cheating is a very digital proposition. You can try to make a move or sneak a piece off the table when your opponent is not looking, but that is certainly cheating and is also pretty easy to identify. There are a very limited number of variables: 32 pieces, 64 squares, two people whose turn to move it might be.
The more complex a system becomes, the harder it is to separate cheating and emergence. If a majority of the players in Risk team up to eliminate the others before slugging it out between themselves, it isn't cheating, even though it certainly radically limits the enjoyment the people on the outside of the alliance might get out of the game. The ability to negotiate your way inside this kind of alliance, or to prevent it from coming into being, is part of the meta skill set around the game, effectively, and so the annihilated minority is getting the sharp end of a gaming mechanic, in some form. One problem with this, if it's a problem, is that it turns your skill set into your entire life. To be a successful player, you need to make friends and generally conduct yourself in a way that makes people want to play Risk with you and to team up with you against others on the board.
Maybe the Parker Brothers got into game publishing after their brother-brother team gibbed all comers at Monopoly. Who knows?
Where this is all going is that the bigger and sandboxier games get, the more it is possible to play cat and mouse with the developers - to see if they have anticipated a particular response to stimuli, or whether unexpected actions can have a positive effect on gameplay - cheating without cheating, in effect.
There's a reason, for example, why characters in games are often employees of some sort of law-enforcement, military or shadowy government agency, beyond generic expectation: it makes it much easier to create a world where you can expect to be told to do things, often dangerous and profoundly unwise things, and be expected to do them. In
Grand Theft Auto 3, conversely, it might be perfectly in character to ignore the plot and just wander about, turning people over for money, and the game allows for that, although it limits how much of it you can see. In order to follow the plot missions, you have to buy into the motivation of the character, who is doing all this often time-consuming, difficult and tedious slogging in order to protect his family, avenge same, and ultimately transcend the narrative of gang violence and police corruption that has constrained his life (admittedly, by killing all the gang members and corrupt policemen in a series of scripted incidents - in a proper sandbox, you could just follow them home, murder them and be done). In ludological terms, the development of the narrative is both the object and the reward of following the story missions, and at the end of the story missions the "reward" is being able to wander around the environment at liberty - that is, to do pretty much what you could to start with. If you time it right - after the gang warfare starts but before the green Sabre, you could live a perfectly happy if limited life in Los Santos - unmolested by the police and still convinced that your homies are loyal and trusted allies.
That isn't cheating, but it is making a choice to interact with the game in a certain way - specifically, by abstaining from "story mode" at a given point. This thought was inspired by discovering that administrators were kicking players from
Left 4 Dead servers for speedrunning - abandoning their companions and making a dash for the safe room. Likewise the opprobrium aimed at "campers" - people who find secluded, covered positions and hide in them
in exactly the way you might if you were trying to fight off waves of undead. Is this cheating, or just ungentlemanly conduct, or simply good environmental awareness? It feels to me as if a game where racially abusing Louis is potentially considered less offensive than holding down the W key and ignoring the screams of your companions is not so much mirroring the end of human civilisation at the hands of a mass of mindless, rage-filled monsters as modelling it.
However. This entire tangent was started by
Robin Burkenshaw, who is doing interesting things with game mechanics. Most of the attention is going to
Alice and Kev, in which he has by building a home for his Sims with no walls or roof created a homeless family. Who are, predictably, having a lousy time. It's the
poverty challenge, basically. There's another level here, where Rod Humble is supervising the creation of complex systems to simulate human misery and making tiny games around married life and Half Moon Bay in his spare time, but never mind.
However, in terms of emergent gameplay (because you have to work pretty hard to create a homeless family, and even then they are not homeless -their home just looks like a park) I was more interested by the experiment in
Space Rangers 2: Dominators. One goal of the game is to become the highest-ranked space ranger in the galaxy. The expectation is that you do this by competing with your peers - who can make the most money, defeat the most enemies, generally behave in the most rangerish fashion in a spacey context. Burkenshaw adopted the more direct method of tracking down and murdering everyone ahead of him in the rankings. This is a lengthy process, and involved a lot of time spent hiding and reloading, but is still a lot less lengthy than the path of relative virtue.
Because of the persistent universe, this has consequences - the bad guys the Space Rangers are supposed to be fighting speed up the conquering. However, the game also heals around it - the Space Rangers academy pumps out new rangers, and the balance of power shifts back. The game's incentive to you to behave as expected, along with goodness, achievement awards and the rest, is that its world is weighted towards plot-directed actions being significant over the longer term. Almost exactly unlike real life, the evil that men do is interr'd pretty quickly; despite the absurd odds, the mechanoid psychosis of the bad guys and their stated intent to dominate (the clue being very much in the title), the desire and encouragement to do the right thing is woven into the physics of their universe.