Grue's Cavern

Grue's Cavern
Location	Level 21–28 of the Dungeons of Doom
Variants	First version Second version
Bones	No
Mappable	Yes
Teleportable	No
Diggable floor	Yes
Diggable walls	No

The Grue's Cavern is a special level that appears in dNetHack, notdNetHack and notnotdNetHack.

The entire level is a non-teleport level and is shrouded in darkness, and the player must avoid or defeat the Grue lurking within to proceed.

Generation

The 'challenge' level generated before the Castle may be a map from either this level or Medusa's Island, and the Grue's Cavern has two layouts, giving it a ¹⁄₃ chance of being generated.

Common traits

Each version of the level contains 18 candles embedded in the walls, two chunks of fossil dark, 9-11 random traps, and various random items. The candles can be worth collecting as light sources to use for driving the Grue away.

Each level also includes two treasure piles. The first is the corpse of an unlucky elven adventurer killed by the Grue and their leftover equipment, including either a cloak of invisibility or a cloak of displacement. The second is a pile of loot like one that might have been left behind by an unfortunate Zork adventurer: a lantern that has run out of power, a sack containing a wrathful silver elven broadsword (doubtlessly of great antiquity), a magic torch, and a platinum bar. (It seems that the adventurer unwisely chose to continue relying on their lantern!)

The Grue will spawn asleep on the downstairs.

First version

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The Grue is generated asleep on the down stair. The locations of the treasures are marked as follows:

• 1, }—One of these spots will contain the remains of an unlucky elven adventurer, specifically an Elvenqueen corpse, a wand of light, a +1 elven broadsword, and a cloak of displacement. A second spot has a ⁹⁄₁₀ chance of containing a blessed potion of healing and a ¹⁄₂ chance of containing a blessed potion of extra healing. The spot marked } is a moat square, so if one of the treasure piles is placed there it will be underwater.
• 2—This spot contains the Zork treasure pile.

Second version

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Treasure locations:

• 1: one of these spots will contain the remains of an unlucky elven adventurer: An Elvenking corpse, a wand of light, a +4 elven broadsword, and a cursed -1 cloak of invisibility. A second spot will contain a regular lich.
• 2: This spot contains the Zork treasure pile.

The Grue is generated asleep one square to the left of the down-stair.

Origin

The level is derived from the classic video game Zork, which contained a Grue that would kill the player if they attempted to travel in darkness.