Small Town Hero by Patrick Neate
Ever since his dad died in a shock accident, thirteen-year-old Gabe’s world has been turned upside-down and back to front. Literally: Gabe has discovered the ability to tell stories which take him into the past, or imagine an impossible version of the present or future that seems as real as real. Gabe has no clue what is going on.
But the answers may lie with his mysterious uncle Jesse, an online game called Small Town Hero which seems to mirror Gabe’s own life, a long-lost grandmother, and the very fabric of time and the universe.