The Rhumgold Sagas: Gateway to the Past

Andrew Timmons discovers his father has cancer and the Guild doesn't want to treat him, even though they have instruments that can do that. He steals one and begins a life on the run. He is chased into a clearing that has an ancient gateway. He breezes through it and finds himself in another world where he has to catch on quickly - to survive. He has landed on his feet on Chimera, in the Antares star system.