I recently started using Zbrush, too. Its really fun and I watch all the videos in youtube to learn. This troll looking good. I recommend you to turning the alpha off while working with clay build brush. Square alfa leaves rough textures. I'll try this timelaps thing , too ^^

Usually trolls are dumb creatures , it has something about the eyes, when they are far from each other it gives the dumb look to them. But in this case this one looks a little more intelligent to me. It is looking smarter then usual. I wouldnt want to mess with this guy.