Abstract: We present an optimization framework for generating diverse variations of physics-based character motions. This allows for the automatic synthesis of rich variations in style for simulated jumps, flips, and walks. While well-posed motion optimization problems result in a single optimal motion, we explore using underconstrained motion descriptions and then optimizing for diversity. As input, the method takes a parameterized controller for a successful motion instance, a set of constraints that should be preserved, and a pairwise distance metric between motions. An offline optimization then produces a highly diverse set of motion styles for the same task. We demonstrate results for a variety of 2D and 3D physics-based motions and show that this approach can generate compelling new motions.