GURPS Powers is a supplement for GURPS Fourth Edition that describes how to create various amazing abilities using the GURPS rules set. It includes a handful of new Advantages, many new Enhancements and Limitations, and many example Powers. The central innovation is the Power Source modifier, a generalization of the Psi modifier from the main GURPS Characters book, that describes where a power comes from (psi, magic, chi, and so forth). A related concept is the focus, a description of the kinds of abilities in the power. For instance, a pyrokinetic has a source of Psi and a focus of fire powers.