The Keep on the Borderlands
B2 The Keep on the Borderlands, Gary Gygax's starter module
Here is the honest exception: this is probably the most common module of all, with a total print run well over a million and a half copies, because it shipped inside both the Holmes and the Moldvay Basic sets. It earns its place because so many players had their very first D&D adventure here.
That huge run makes it the friendliest place to start a collection. A complete copy, with its map inserts and intact cover, costs a fraction of the rarities here and is still a pleasure to run.
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