Here's a quick overview of the main character so you don't need to go through the five-chapter introduction.
The MC is a Ghost — a Terran psionic operative who doesn't rely on the Warp. Terran psionics draw power purely from their own mind, which makes them completely immune to Warp corruption. Their abilities are more limited in raw magnitude compared to Warp-based psykers, but far more stable
His observable psionic talents include telepathy, mind control, telekinesis, pyrokinesis, and psionic storms. In extreme situations he can also bend or modify certain physical laws within a localized area, altering things like inertia, kinetic transfer, or thermal behavior for a short period of time.