Slidey feet, no-one likes that. The terrain adaptation sop (and its equivalent feature in dops later) can lock feet to the ground when they're meant to stay still, which can help crowds look more natural in most cases (and look really funny when terrain gets too uneven, all goes very Monty Python Silly Walks...)
A look at facial rigging with animated feature films in mind. We will create a fully functioning face rig, looking at one element at a time so that anyone can follow along with the workshop and get something out of it.