According to Greg Svenson, it was back in 1972 that Bill's character made the discovery what would turn him into the Blue Rider while the group was exploring the deepest levels of the Blackmoor Dungeon. There they came across an island surrounded by lava:
"William wanted to jump down to the island. Svenny was opposed, mostly ss self preservation thing. I couldn't see how we would ever get off the island if we managed to get there. William jumped anyway and managed to land on the island. The rest of us stayed on the ledge and watched. Mello took some chalk and wrote "Kilroy was here" along with the famous sketch of the head peering over a wall on the wall of the ledge.
The dragon posed a puzzle for William. I don't recall the details, but he solved it and was was rewarded with a blue suit of magic armor and mechanical horse. I have always thought of the armor as a dark metalic blue, but the description was just blue. The armor was more like powered battledress then a suit of plate armor, for Sci-Fi fans. William doned the armor and somehow was back with us on the ledge. We all traveled back out of the dungeon."
Mello the Halfling (Played by Mel Johnson) was one of the Blue Rider's steady companions. The FFC relates how it was the armor that changed the Blue Rider's demeanor into that of a selfless hero turning him perhaps into the first Paladin or Cavalier type character in the history of D&D. After performing many heroics in the Blackmoor campaign, the Blue Rider was eventually made town constable of Blackmoor Town.
More discussion of the origins of the Blue Rider's Armor.
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