His early hobbies included slot car racing, a fascination with dinosaurs and the drawing of fictional maps.

After graduating high school both he and his future wife Sharon went to work assembling circuit boards at Crossby Electronics.

They did a great deal of GlenAyre Electronics’ contract work during the 1970s and were responsible for the bulk of circuitry installed at the former BC Hydro tower located on Burnaby Mountain.

After graduating Douglas College he transferred to Simon Fraser University, where he co-founded SPLUD, the Society for the Protection of Large Unpleasant Dragons.

[2] Crossby was similarly attracted to the arts; he was an accomplished guitar player and composer who often performed at family gatherings.

[2] Not long after arriving in Canada he met his future spouse, Sharon MacLeod, a close friend of his sister Susan.

Throughout that year CGI published a series of booklets called the Encyclopedia Hârnica, consisting of the history and background of several regions of the island of Hârn.

Also in the early 1980s, Columbia Games released the Hârn Regional Module, which included a massive, full-colour map that attracted many reluctant players to the system.

One section of HârnWorld, for instance, laid out a complex model for generating weather patterns that affected the entire planet.

At one time Hârn fandom also had a thriving mailing list called HârnLine, also known as the Duffleboard for its moderator Rob Duff.

Columbia Games moved to Washington state, and Crossby stopped writing new material for the company in 1994; fans began more and more to add expansions they created (called "fanon") as no more official material was being produced for the setting, and Crossby also began working on his own version of Hârn.

During this period he published nearly half a dozen products, including his own extension of the basic rules called HârnMaster Gold.

Columbia games continued to produce Hârn products in defiance of the contract dissolution up until Crossby's death and beyond.