How not to suck at unit design

Alright. Here is the first step.

1.CLOSE YOUR 3D PROGRAM.

Step one of the design process is never, ever “get started”. Ever. Some people think they can get away with winging it; you can't. Every model I ever made on impulse for Paradox was eventually replaced, without exception. Ever unit that went through the proper process has stayed. This is not coincidence.

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Before you do anything else, make sure you know the rules of your universe and the faction you are creating this vehicle for. Factions need to be “designed” the same way units do, so that is where we will start. After the gameplay stuff is worked out (determining faction-specific weapons, general level of technology, etc etc) you start by coming up with lists of features that this side has. What kind of shapes do they favor, are they rounded, sharp-edged, somewhere in the middle? Are they fast, slow, strong, tough, fragile or weak? What sort of technology do they have? Do they have access to small computers, electric engines, atomic power? Start coming up with visual features that can be cobbled together to form a whole. Make a list going from basics to specifics; it should look something like this.