Grellkin are a bit larger and more mischievous than grell. Grellkin use tactics similar to grell, though the occasional grellkin wields a manufactured weapon. (MG 97)
The grellkin have recently moved into Shadowglen. Tarindrella the dryad believes that the Fel Moss these grellkin carry has something to do the with corruption of Teldrassil and its creatures.