This post crosses from computer games to tabletops and back again.
Let's talk about how a game latches on to the mind of the player.
Last post, I explained how I think the thing which sets games apart is a weighted reward/penalty feedback loop. Example: in an FPS, the feedback loop would be the running around shooting people. The weighted reward/penalty would be health damage - both yours and theirs.
To make it a little shorter to type, I'll call these "play loops".
Here's the thing: in order for a play loop to catch a player and be fascinating, the player has to appreciate the rewards and penalties it gives him. I don't much like racing games, largely because I don't appreciate their rewards - simply being a little faster or a little slower doesn't mean much to me.
There's nothing wrong with racing games. It's simply that the play loop doesn't catch me.
There's two basic ways of getting a player to appreciate a play loop, and games commonly use both. The first is "immersion", the second is "support loops".
Using graphics, story, conversation, music, and so forth, a game designer can make the player fascinated by the world the play loop exists in. The linear progression of nearly all stories in nearly all games is a method of drawing the player into the world of the game.
What this does isn't the same as it does in the movies. Rather, it is the same, but it is applied differently: once the player is immersed in the game world, the rewards and penalties relative to that world have a much deeper hook into his mind. To give a tiny example from one corner of this broad idea, if you want to know what's going to happen next, you want to win. Suddenly, the feedback matters.
Now, it's actually a bit... off. In certain quantities, the wish to advance the game wholly replaces the wish to play the game. This happens more frequently than most developers are comfortable with. Players say, "Damn it, can't I just skip this level?"
Yow! That's bad! They wish you were a movie!
Occasionally the reason for this is having a pretty poor feedback loop - the game is too simple or buggy. However, most of the time, it's for a more subtle reason:
The play loop's rewards (health, items, levels) have been replaced in your mind with the story's rewards. The story has only one type of response: advance or not advance. This is not strong enough to support a play loop - it turns the game from a weighted reward/penalty feedback loop into a simple feedback loop. Unacceptable.
By understanding that what drives a game is a play loop instead of a simple feedback loop, you can make your immersions come in distinct reward magnitudes, just like a full play loop's.
One example of this is TimeSplitters 2: each time you beat a challenge, you get a few rewards. But the rewards you get are based on how well you beat the challenge. It's not simply "kill these zombies successfully and get a new hat", it's "kill 30 zombies, get a new hat. Kill 40 zombies, get a new hat and a new level. Kill 50 zombies, get a hat, level, and new character!" This is on top of the subtle but important feedback of bronze, silver, gold and platinum trophies - clearly displayed as a sign of the magnitude of your victory.
Actually, I'm a little irritated at the system, because I really suck at some types of challenges. Like picking up smegging bananas. I hate racing games.
It might have been a good idea to offer alternate challenges or something. It might have also been a good idea to display what you could win at each level of victory, but that's besides the point. The real point is clear: they offer rewards in which the magnitude of your victory matters. This means that the play loop remains a play loop. The reward has shifted somewhat, but still exists as a complex reward instead of just win/lose.
That is a support loop. It's another feedback loop, often a very simple one, which interacts with the main loop to increase the complexity and longevity of the main loop. This is very common. Nearly all non-casual games contain at least two support loops, if you can even distinguish which ones are support and which one is main.
I could analyze other games - or more deeply analyze TimeSplitters 2. Like all complex systems, it deserves more than I give it here. But that would be even more boring than this essay already is, so let's move quickly on:
When you create a game - no matter what type, it's important to offer this complex reward. The game cannot simply progress, because that means they'll either lose interest in the play loop or lose interest in the progression. Either way, it's totally inefficient.
So, for example, a tabletop RPG. The "main loop" is the incomprehensible morass of rules used for fighting, supported by numerous support loops for traps, treasure, religion, leveling, and everything else under the sun. (Most tabletop RPGs have at least 8 support loops.)
The basic idea of most tabletops is that they include all that crap because it means that a clueless GM can simply plug it in and let it chug. The players will theoretically latch on to these support loops and drive themselves to accomplish whatever goals are made likely.
The thing is, this is unreliable and inefficient.
Most GMs have a problem "controlling" their players. I hesitate to call it "control": a better word would be "guiding". Their players don't bother to follow the GM's nicely laid-out plot.
I don't have that problem. The reason is simple: I don't use all the default support loops. I create my own loops which follow the rules I laid out above.
Default support loops offer brutally generic feedback. Many players will have them memorized. Their rewards are too powerful while simultaneously being too simple. How many times have you heard a player say something like, "I want to get to level six!"
They've replaced the main play loop's rewards and penalties - consisting mostly of HP finagling and some resource management - with a simple "treadmill through to level six". That's bad.
Your support loops should be the guiding light of the game. To do that, you need to make other support loops subordinate to it. In my opinion, this means ditching all the crap that comes in the giant rules tome. You don't need their leveling, their item lists. You certainly don't need their whole world! Even if you're not able to think up a world on your own, cut away all (and I mean all) the pieces of the world you aren't using. Just don't mention them.
Then you bring in your own support loops. These loops react to how well or how poorly your players do. Don't hook your support loop onto the back of some other support loop, either: make it the dominant loop. It touches and reshapes all the other support loops. Rewards and penalties should hit every other support loop in addition to itself: weapons, experience, information, allies, or anything else you can think of.
If the players seem to be thinking too much about one of the less important play loops, such as levels, spin the other play loops. Give them jack shit for XP: instead reward them with information. Or allies. Or items. Or glory. It shouldn't take much before the player gets interested in one of the more active loops - that's how a player's mind works.
Honestly, I can't say this will work for you - or anyone else. But it seems to work for me, and I believe it is the fundamental "gameness" of a game.