Mechanics & Features

Paradigms imply the rules of a game but the mechanics define them. In a way, mechanics are the toy within the game. Momentum is a mechanic, so is matching three blocks to remove a set, reloading a gun, building a barracks out of wood and iron, or anything else you can do in a game. If the user can change or affect something, it is a mechanic.

Mechanics are specific and technical and the details generally constitute 'too much information' for anyone other than programmers and designers. For everyone else there are features which are just lumped-together groups of mechanics that gloss over the specifics.

An experienced designer is thinking about mechanics from the moment the game concept comes crashing onto the scene. If someone says, "Hey, let's make a game where you're God!" and everyone agrees that's a great concept, the designers had sure better be working to define manageable mechanics before everyone shakes hands and starts work.

A common, unspoken, belief in mobile game development goes like this: The more features and mechanics in your game, the better it will be; this is because, the more things there are for the player to do, the greater the value of the game.

The above statement would be completely true if making games was not a process limited by time, money and user attention. The most important thing a designer can do is decide which features add up to a compelling whole and which features are expendable.

Being a designer is like being a director because, at the end of the day; ideas are cheap, artistic vision is not. Programmers can view the design as pure mechanics, producers as pure features, but the designer must see more.

Beyond the functionality and the features, it is the designer's job to use experience and vision to pare down the proposed design into something which is aesthetically pleasing, poses meaningful user decisions, adheres to an intuitive interface, and creates a cohesive, balanced experience of tension and release.

Interface

The final layer of game design is interface. Interface is the physical means, and audio-visual cues, through which the player interacts with the game mechanics.

Traditionally, interface is about buttons, but it might also include an analog stick or two, mouse, microphone, accelerometer, plastic guitar, or futuristic motion-sensing glove.

At its simplest, interface design is just matching inputs to the mechanics, but the task quickly becomes a balancing act: don't overwhelm the user with too many new inputs, avoid difficult input combinations or prohibitively precise timing, and stick to a consistent, easy-to-remember theme.

With mobile phones, interface is a significant challenge; phones aren't built as gaming devices. While designing Guitar Hero World Tour for mobile, I quickly confirmed that adding just one more button for a kick-drum created gameplay significantly more difficult than the three buttons the player experienced on guitar. Players often had to change their entire method of holding the phone to accommodate the added input.

To simplify the addition, we allowed the entire bottom row of number buttons (7,8,9) to be valid kick-drum inputs and then went further and filtered the note-data so that no multi-note chords would occur on drum tracks.

In the end, this additional simplification actually helped create unique gameplay between the guitar and drums modes: the challenge of guitar was in managing increasingly complex chord transitions and the challenge of drums was in the fast succession of single notes over a wider range of inputs.

As much as we may wish it wasn't true, interface exerts an upward influence on the mechanics; a design only works if the user intuitively understands how to interact with it, so accommodations must be made for the sake of the interface. Entire books have been written on interface design and usually the conclusion is the same: the goal of the interface is to make the interface as transparent as possible.