A mixing optic combines a variety of features to enhance the brightness and uniformity of the light emitted from a combination of different color light emitting sources. The mixing optic may include a parabolic reflector that redirects low-angle emissions, a reflective waveguide that mixes the light spatially, and a diffuser plate that mixes the light angularly. In an embodiment, the output of the mixing optic exhibits a substantially Lambertian output pattern of a substantially uniform mix of colors, exhibiting, for example, the light output pattern of a single white light source.