There in the shadows on a large flat stone sat a tremendous goblin with a huge head, and armed goblins were standing round him carrying the axes and the bent swords that they use.
-Over Hill and Under Hill, The Hobbit
That's the extent of the book given to describing the Great Goblin.
I've been thinking of the goblins as having some sort of physical development that kicks in once they hit adulthood. Because they are so warlike and so violent, very few actually reach full maturity and become these larger and more powerful creatures, which would naturally obtain some sort of leadership or even deification within the tribe. These are the Great Goblins, who rule their colonies, lead in their wars, breed with the gross goblin women, and pass on their superior genes. They also have the darkest, reddest caps.
I am still playing around with how I signify these changes in the design, and specifically how I add them onto the base goblin design. I like tusks and horns, since those are developments that exist in natural animals and signify maturity. I'm also expanding on the pig/bat/mole-like nose that the smaller guys have. The second page up there contains a few solid jumping-off points.
In other news, Picturebook Report has gained a new member in Chuck Groenink! Good news for everybody.
I also have to direct you to this post on Kali's blog, which talks about the amazing sketchbooks sent to us by Mel Chao and Mark Grambau of To Boldly Fold. It is truly an amazing piece of work, and for someone whose artistic talent stops at two dimensions, seeing the care and craftsmanship that goes into these books is truly humbling. I will talk more about the book once I start to work in it.