- First Appearance: 02: Into the Greyspine Mines
- Armor Class: 12
- Challenge Rating: 2 individually, 7-10 for first encounter
- Blindsight 60 ft
- Speed: 40 ft
- Avg/Max HP (MM): 21/30
- Killing spell of 14 cold damage (29 saved) by Tiberius
Consider Intellect Devourers (IDs) as Mind-Flayers Lite: If they take any magical damage, they go down pretty easily, but they can still kill brute-strength characters in a couple of rounds. Grog was fortunate that Tiberius acted so quickly; another round, and Grog would have been officially brainless and out of the game. This first ID provides just a taste of what the low Int-based characters have in store in the Underdark.
IDs usually get their armor by taking over the body of their host, and the host becomes the meat shield. In this form, the damage-dealing capability of both the body and the ID are minimal. Once the ID has been expelled, the body dies (brainless), and the ID regains its offensive abilities to aid in taking over a new host. Unprotected IDs have resistance to all nonmagical physical attacks.
The Duergar made the battle a little more interesting, but because they didn’t use all of their abilities, and because the ID’s health was on the lower end of the scale, it’s clear that the encounter was more to peak interest than form a serious challenge. For that reason, the challenge rating could be calculated around 7 or 8, but XP gained was probably around CR 10.