When a nerd is stranded in another dimension
DOUG AND THE TRANSDIMENSIONAL LAWNMOWER
Doug was minding his own business, driving his trusty lawnmower when it hit an ordinary looking stone that turned out to have extraordinary capabilities.
DOUG A kind, shy, inubstrutive daydreamer who lives for his hobbies of comic collecting, video blogging and gaming. He needs to change in a hurry if he wants to live.
RIF is a warrior dragon rider because she is brave, trustworthy and true. Because she is sulky, obstinate and unpredictable, she can be one in the desert.
STELIO A dragon currently hired by the portal police. Dragons are terribly useful thanks to their flying, defence and tracking abilities. Their biggest drawback is their constant search for food, which sometimes shortens their partnership with their riders. Stelio does make it a point to never eat a friend, but since he does not have any, it doesn't make any difference.
Doug, Tik and Stelio have to trek across the desert to reach the capital of the Husa empire and the way is fraught with perils (giants, rock cats, zombie robot princess, etc). Husa has everything an evil could wish for : smoldering deserts, impassable mountains, magical jewels and evil minions aplenty.