Description:

Create-a-Sim (CAS) is the character (Sim) builder, where the polygon 3-D models of Sims can be modified. New features include the ability to change footwear and head wear separately and to add freckles. Sliders have replaced prior functions in CAS. For instance, muscular and obesity sliders replace The Sims 2 system of three body types (fit, regular, and fat). Skin color, hair, voice pitch, clothing texture, and other things can also be adjusted on sliders.

The original system of percentage bar personality points has been replaced with a system of traits. These traits control the way Sims behave. For example, a clumsy Sim may break items while using them and a hot-headed Sim may annoy another Sim at random. They also open up special interactions which might not be available otherwise.