From publisher blurb:
The Shiftsteel Symbionts are a unique breed of cybernetic organism. They are humans whose bodies and souls are bonded, on a genetic level, to alien alloys. Created by a series of interlaced time paradoxes, Shiftsteel Symbionts are gifted with an assortment of unique superhuman powers and a unique perspective on space/time.
This PDF expands dramatically on the Shiftsteel Symbiont race, originally presented in the Psi-Watch Campaign Setting. Inside, you’ll find new racial traits, dozens of new race-specific talents and feats, and plot hooks. In addition, you’ll find out what Shiftsteel Symbionts look like in Otherverse America and Galaxy Command.