When creating Torchlight & Torchlight II, we had both a team of internal artists and an art house in China we outsourced some of our work to. Part of my job was establishing the baseline/template for others to work off of as an example. Once we had our target established and our pipeline for asset creation down, my focus shifted into providing feedback and ensuring everything reached the quality bar of a final in-game asset.
With our Torchlight style, we focused a lot on how to emphasize and push the stylization of our character anatomy. This shows where we push the weight and mass on distinct body types.
Examples of character class skill concepts for the "Engineer" character.
We generated a considerable amount of prop sheets (like the 2 above) for Torchlight 1 and 2. Concept Artist Kyle Cornelius and I worked in tandem on these, with his focus on design and line work and mine on conceptual design, how they fit into 'world lore', and color rendering.
For an MMO project called Mythos, I created a number of conceptual mockups with notation for our environmental artists and level builders for a wide variety of settings.