[SDriver]

IIRC, there are also Drow in the catacombs at the end of A2 as a "non-tournament" encounter. I don't have it at work with me.

I think at least some of the dippiness of the "puzzles" in the A-series (which I've always had fun running) stems from its origin as a set of convention tournament adventures. (1980 GenCon? Don't honestly remember, although I think there was an article about it in Dragon #49, the first Dragon magazine I ever bought.)

Thus the text-adventure "solutions" like conveniently placed giant mushroom caps, along with bizarre set pieces. The encounters are presented as a gauge of how efficiently a given group of players can overcome a preset obstacle. The initial stages of the A-series finale, In the Dungeons of the Slavelords, are almost Zork-like, to the point one worries about wandering grue.

Ghost Tower of Inverness and Hidden Shrine of Tamoachan spring to mind as other gonzo tournament-style adventures with weird-ass set pieces. ("CHESS ROOM!!!")

None of this, of course, explains White Plume Mountain.