Sinix is a concept artist previously employed by EA, FuZion and various other studios. Apart from being a very capable illustrator and a lovable character he has also provided free of charge this YouTube Channel. It has some awesome tutorials, giving a really clear insight into the way he creates vivacity in a painting. The portrait painting series is definitely worth a watch, and is filled with broadly useful information. Anyone who's tried to paint a lively and interesting skin-tone knows it's no easy task- in this series Sinix explains his own very effective method.