“How to make Dota 2 Characters” Sheet
Valve takes an extra input at coming up with this PDF on how to make characters. What surprises me more, its that they are sharing around this great resource! Did we need to know? Its a great thanks to me the detail that they have gone into, from silhouette, colour, perspective to topology formation and gradient. Great work Valve. Its stuff like this that makes work being even more appreciated.
Dota 2 Character Art Guide

Colour examples in characters, Dota 2

Character Silhouettes from Dota 2

Geometry Best Practices