O2: Blade of Vengeance (1984) is the only other entry in the O line of modules, so I guess one-on-one D&D never really caught on (though there is a multi-volume series of one-on-one D&D pick-your-path books, which I have to cover one of these days). If the little Union Jack didn’t clue you in, this was produced by TSR UK.

Blade of Vengeance dispenses with all the tournament nonsense from O1. In this, you’re a 7th level elf (this being basic D&D, elf is is both a race and a class). What starts out as a pretty standard “what monster killed my family” plot actually evolves into surprisingly transformative chosen one story. There’s some cliche bits, but overall this is a solid scenario.

Of special note is the art by Jes Goodwin. A practiced eye can tell at a glance that this guy would eventually wind up illustrating Warhammer and, in fact, he pretty much defined the look of 40k. I frickin’ love his work here and am currently cursing the fact that Warhammer is such a huge hole in my RPG experience.