Gorcrows were essentially large ravens in the I.C.E. Age bestiaries, which were used as familiars by evil "followers of darkness." They still exist in the background in The Graveyard near the burial mound of Kestrel Etrevion, where implicitly they are used by ghoul masters to scout the surface for intruders. The ghoul masters would be directing lesser ghouls to leave the bog to attack intruders, as in the Rolemaster lore ghouls were subservient to the orders of more powerful undead. The difference between ghouls of varying power was only age, so the weaker ghouls were made from more recent trespassers.
I.C.E. Age Example
Gorcrows come from Creatures & Treasures I (1985), page 44, but not the Shadow World Master Atlas: Inhabitants Guide (1989).
[Graveyard] The trail turns at a sharp angle, causing you to move with greater purpose. The air is sweet with the earthy scents of rich soil, growing things and long-buried secrets. A lone gorcrow croaks overhead and alights upon a mysterious mound of earth to the north. Obvious paths: north, southwest [Graveyard, Top of Mound] From the lofty perch atop the burial mound, you look out over the lowlands and marshes to the south and west and the desolate plateau to the north. Facing southeast are the ominous graveyard, unquiet crypt, and the gates and cemetary walls beyond. The ridge is narrow and uneven, with little room to maneuver. Startled by the cawing of a nesting gorcrow, you realize that any distraction from keeping your balance would be courting to disaster. You also see a narrow gully and a pool of stinking mud. Obvious paths: down
Behind the Scenes
Gorcrow is a real-world term descended from Old English meaning carrion crows. It is not something that can be copyrighted, but the implied detail in the game that they are used by "followers of darkness" to "harass and spy on their enemies" comes from the I.C.E. source books. There is also reference to gorcrows in the Feymist Cemetery, but this is post-I.C.E. Age without the implied meaning.