HEADLESS DRONING APE

"The size of a large gorilla, the sussurus appears at first sight Jjke a headless ape which moves on all four limbs. In fact the 7ft tall beast has no external organs, nor anything resembling a head,"

The sussurus, a geometric humanoid creature made out of reflective material, its body is full of holes that wind blows through to create a whispering sound. source: Forgotten Realms wiki
origin: Fiend Folio (1981) Don Turnbull, Advanced DND 1st edition page 84