Some non-spoiler points about Night Below from the DMsGuild:
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Origins (II): The Return of D. Night Below: An Underdark Campaign (1995) is clearly intended as a reinvention of Gary Gygax's original series of "D" adventures. Like that primordial campaign,
Night Below is set in a peopled underdark with monstrous cities and entire civilizations beneath the earth."
"Night Below even includes an Underdark ocean called "The Sunless Sea", which is an obvious homage to the otherwise unexplored locale mentioned in D2: "Shrine of the Kuo-Toa" (1978) and D3: "Vault of the Drow" (1978). Given Carl Sargent's past work as the main architect of Greyhawk, this has led some to speculate that
Night Below was originally intended as a Greyhawk campaign — or perhaps as a trilogy of adventures, for its clearly broken up into three equal parts. Unfortunately, author Carl Sargent would not be able to speak to this speculation."
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Adventures Styles: An Adventure Path. Night Below follows in the footsteps of the "D" adventures in another way: it's early adventure path, meant to bring players from first level to somewhere in excess of tenth. However unlike modern adventure paths,
Night Below doesn't really contain enough challenges to level the characters up.
Night Below alludes to this by suggesting that players use "side-plots" and "mini-adventures" to flesh out the campaign and give it more verisimilitude. Online,
Dragon editor Dave Gross was more adamant, saying, "Don't forget that it's highly recommended, even necessary that you expand the Night Below campaign with short adventures". Of course, he suggested
Dungeon Adventures as a great place to find those mini-adventures."
"Adventure Styles: Locale-Based. Night Below is largely a locale-based adventure. There's a sandbox of a town for the first section, then a ruins crawl, a mine crawl, and lots of underdark crawls."
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Exploring Greyhawk. Though
Night Below is a generic adventure, the presence of a Sunless Sea has led many to place it in Greyhawk, beginning on the opposite shore from the "D" adventures."
Night Below: An Underdark Campaign (2e) - A missing mage... A ruthless band of kidnappers... A sinister conspiracy... Night Below, the first epic campaign adven
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