Orthogonal Elements

Allow me to misuse a math term here.

The elements of a game should multiply the game's space, rather than add to it. The elements should be qualitatively different rather than quantitatively.

An example is chess: if we consider the different types of pieces the elements, their moves are orthogonal. Vertical. Diagonal. Halfway between vertical and diagonal (the knight). A single space.

Math purists will point out that if chess was literally orthogonal we'd have pieces that could move sideways and pieces that could move vertically and that would be it. So what I really mean is elements that are qualitatively (rather than quantitatively) different.

Lately I've been thinking that this may be one of the deepest, most fundamental principles of game design. It is one method to create MeaningfulChoices. And the discovery of methods this wiki's primary mission.

A variation may be "Orthogonal Mechanics" - see MechanicsThatCombine.

Another could be "Orthogonal Resources" - SeparationOfResources.

I have no evidence but I believe it's when you have orthogonal elements that EmergentStrategies are more likely to develop.

I'm not sure, but I think RockPaperScissors may be a specialization of this pattern. The value of each element is equal; the quality of each element is not.

To put this rule in practice; if you're designing a fighting game where you have three kinds of attacks and no defenses, adding a block or dodge is more interesting than adding another kind of attack. Adding an attack that does a different kind of damage (stun, knockback) other than reducing hit points is more interesting.

Or, if you're designing a strategy game; having units that scout / have visibility range / have ranged attacks but not close attacks / have close attacks but not ranged attacks is more interesting than adding more units that just attack.

This rule applies more to pure, abstract games than simulations. In a simulation you're striving more to mimic reality, and that may mean several types of guns which all have subtle differences.

Some day I'd like to have an original idea: Harvey Smith of Ion Storm beat me to this with a GDC presentation I swear I hadn't heard of when I wrote this page: http://www.ionstorm.com/archives/oldIon/gdc2003/