A large flightless bird; 120-150 cm TL. Head and neck: Almost bare head and bright blue, but color changes depending on mood; neck red, yellow or orange with one wattle; distinctive casque variable in size and shape, grey to black; before eye and throat deep purplish blue; eye yellow to brown.
Body: Body greyish black, wings greatly reduced.
Limbs and tail: feet with 3 toes; Legs powerful and long brownish grey to dark olive; feet grey; tail very short, brownish black.