More frequently, the Grey Man is encountered in physical sensation, but without a true physical form. Sensations of this type include vast, dark blurs which obscure the sky, strange crunching noises, echoing footsteps which pursue the listener, an icy feeling in the surrounding atmosphere, as well as a physical feeling of a cold grip on, or brush against, the observer's flesh. There is also a high pitched humming sound, or the Singing as it is sometimes called, which is associated with Ben MacDhui and the Grey Man.
Additionally, the Grey Man has an extremely powerful psychic effect. Visitors to Ben MacDhui report a feeling of overwhelming negative energy. Occasionally this is described as extreme lethargy and despondency. More often, it is typified by acute fear, apprehension and an overwhelming panic, leading to suicidal thoughts or physical flight from the area. Generally, this fear is accompanied by the physical sound of echoing footsteps chasing the observer, and sometimes the sound of a resonant and yet completely incomprehensible voice which seems to be faintly Gaelic in nature.
Curiously, the Grey Man has a distinct area of influence. At a certain point in their downward flight all observers report that the negative energies and feelings of fear end as abruptly as they began. The Grey Man has most often been encountered within this century by mountaineers climbing in the Cairngorms. He has also been described in several books, including Affleck Gray's The Big Grey Man of Ben MacDhui and F.W. Holiday's, The Goblin Universe.