For many in the gaming world he is best known for his Hero Games work but I was most familiar with his work for TSR, most notably being the force behind three of the most noteworthy D&D products of the late 80s and early 90 (along with several other products he wrote):
- GAZ1: The Grand Duchy of Karameikos (1987)
- Dungeons & Dragons Hollow World (1990)
- Dungeons & Dragons Rules Cyclopedia (1991)
The Grand Ducky of Karakeikos was a detailed look at the default starting area of play in the D&D "known world" (later renamed Mystara). The Hollow World gave us a good measure of pulp with the lost civilizations of the known world (as well as dinosaurs) finding their way into the inside of the globe.
It was the Dungeons & Dragons Rules Cyclopedia that was his masterpiece. My brother and I, both D&D fans, wondered how he got TSR's ok to produce it. While the AD&D 2nd edition game was just beginning to produce its first "splat books" the Rules Cyclopedia for the parallel D&D game was (and remains) one of the most complete gaming books ever made. Over 300 pages of small-font rules, optional rules, monsters, other planes, magic items, information on the default setting, paths to immortality. Armed with that one book you could have a complete game lasting for years and years. It was not an introductory book that gave you the basics and expected you to move on to other books - it was incredibly complete. Allston took nearly two decades of D&D games and versions and consolidated it into the most complete version the game has ever seen (or has seen since). Wizards of the Coast has been reprinting many of the old TSR versions of D&D and AD&D - I really hope this is something they get around to reprinting.
Eventually Allston moved on to producing fiction - some of it his own, the bulk of it being media tie-in fiction, largely in the Star Wars universe. I'm not a huge consumer of media tie-in fiction, though once upon a time I was. I did I followed the early Star Wars tie-ins like Heir to the Empire but the volume was far more than I could keep up with, something that became especially true when the New Jedi Order series came out. Allston wrote the Star Wars novel Betrayal, taking place after the New Jedi Order and he had the difficult challenge of launching a new series that would be accessible to people who were not familiar with much of what had gone on before. I actually did read Betrayal several years ago and found it an enjoyable read, showing the first steps of a man going down a dark path with the best of intentions.
I never had the opportunity to meet with or correspond with Mr. Allston but he made contributions which brought me a great deal of joy - indeed, which continue to do so to this day.