By D. Daniel Wagner
A new monster for the original Dungeons & Dragons game
Transcribed from the Manual of Aurania (1977) with permission from the author
Hit Dice: 15
Armor Class: 4
Number Appearing: 1
This huge monster is humanoid in shape and extremely ugly. All characters that see this monster must make their saving throw against Fear (use Dragon Breath table) or run off in a random direction in blind fear. However, as it is known that Fighter types are braver than Magic-Users, Fighters add plus one to their saving throw and Magic-Users must subtract one and Clerics and all others save normally.
Also, all characters must subtract an additional five points from their saving throw the first time they meet th ecreature. The character(s) who kill the "Grue" are proof against its Fear spell thereafter. If the monster isn't defeated, all characters continue to subtract five points away from their saving throw, which must be made every turn fighting the "Grue".
"Grues" have a magic resistance equal to a Balrog's. A "Grue" does 2-20 points of damage plus one life level when one hits. A "Grue" is also followed by a black cloud that nullifies the powers of Good Luck charms, Spells and the like. "Grues" also fight down one level from normal.
"Grues" aren't very smart and are rather lazy. Movement is 13 inches a turn. Lair 100%. Alignment is chaos.
* * * * *
(1) For reference, here is the magic resistance of a Balrog:
"There is a high probability that spells will not work against them. To determine success of spells use a base of 75% resistance at the 11th level and adjust upwards or downwards in 5% increments, i. e. a 12th level Magic-User would have a 70% chance of resistance."
This appeared as part of the entry for Balrogs in the original printings of Monsters & Treasures, Vol 2 of OD&D, but was later deleted when the Tolkien estate objected. IIRC, it is the first conception of "magic resistance" in Dungeons & Dragons.
(2) Playing at the World discusses the Manual of Aurania on pages 558-559, and in a footnote writes "One notable monsters in the Manual is a "Grue" ... Fans of the later computer game Zork pay heed. The grue figured previously in Jack Vance's Eyes of the Overworld" [aka Cugel the Clever], which can now be found as part of the omnibus Tales of the Dying Earth. The grue never appears directly in Vance's stories, and is only referenced cryptically.
See also the wikipedia entry for "Grue (monster)" for more info on Zork grues.
In 1983, four types of "Elemental Grues" appeared in TSR's Monster Manual II.