I posted these on a forum recently. I can’t claim them as original thought, but I have found them to be my most useful heuristics in filtering game design ideas:

Everything Rests on the Core Loop

Sometimes called the “game mechanic” or the “30 seconds of fun,” the core loop is the series of actions the player will perform over and over again in the heart of gameplay. The core loop of Gears of War might be: 1) Encounter bad guys and take cover 2) Move to a good attack position 3) Kill the bad guys using a selection of your weapons 4) Re-arm and move on.

Everything else – vehicles in a shooter, dialogue in an RPG, cutscenes, minigames, QTE’s, set-pieces, traversing an empty environment, etc – it’s all pacing for the core loop. If any of these elements were solid enough to stand on their own, they would be their own genre. Sometimes they are, like vehicles in a driving game, but often they aren’t, like dialogue or QTE’s.

Every other aspect of the game – the art style, the story, the amount of content – everything needs to gel with that core loop. We talk about an elegant alignment of features as the key to creating a sublime play experience. The core loop is your initial axis to align to.

It doesn’t matter what else you have figured out, if you don’t know what your core loop is, you are up a creek. If you are spending all of your pre-production time figuring out what the story for your game is, the marketing plan, the art style, but you don’t know what your core loop is; STOP. Figure out what your core loop is first.

A great shortcut is to steal somebody else’s. This is how most games get kicked off. Developers borrow the core loop from their previous game or somebody else’s. But, be careful, because now you have to over-deliver on every element surrounding your derivative gameplay so that you somehow elevate the total experience. Minor twists on proven core loops can work, but they can also backfire. It’s best to figure out which situation you’re in as early as possible.

In non-linear games you also need to consider the mission loop. In MMOs this is the quest loop. It will usually include several iterations of the core loop. RPGs are an exercise in mission loop trumping core loop.

A great core loop with supporting features is what creates a wonderful, “flow” experience. Know your core loop, it is the soul of your game!

Design to your Constraints

Can it be done, done easily, and done well? Don’t propose features that push the technology in ways it won’t easily go. You only get one or two of those features a game and chances are you aren’t the guy who gets to make those bets. Instead, understand your tech and the capabilities of your programmers. How much money, time and people have you got to spend? Is your design worth it?

This sounds like common sense, but these constraints are moving targets, and this is exactly what makes design a important skill and not blue-sky, schoolboy-daydream, tighten-up-the-graphics-on-level-three, wouldn’t-it-be-cool-if, bull crap. The farther along you are in production, the more you must design to your constraints.

There is the rare occasion, late in a product’s development, where a risky new feature is worth it. Sometimes you don’t know your game until then and its impossible to come up with those brilliant ideas before you do. But that is a rare gem. When you’re working on a game day to day, you have to design to your constraints to get anything done. The best designers on the job are proposing 10 easy wins to every risky bet, and most of those easy wins are directly touching the core loop.

Games are often designed incrementally, through thousands of little decisions that result in little improvements. Designing to your constraints will get you down the path to a fun game that much more quickly. It’s the job of technologists to loosen these constraints and open up the possibilities, and it is the role of prototyping to cheapen the risks of those big bets that break the constraints.