Dimension Six, Inc. and written by Davy Davis. Or maybe I should say adopted, since it's based on a piece of sixteenth century European literature. I picked up this obscure D&D product at a game store in a Denver mall about 30 years ago on a church ski trip.
Orlando Furioso. I never actually ran it as a DM or went through it as a player. But I've read it a few times over the years. One interesting concept is that it includes "pre-rolled" saving throws, attacks and
damage for all the monsters in the module, the idea being to make the tournament as consistent as possible among different participants.