Type Eight, the Challenger or Protector, is placed in the body triad with Nine and One, and it is the type that expresses the triad's anger outwardly and immediately. Its basic desire is to protect itself and to determine its own course, its basic fear is of being harmed, controlled or violated by others. Its passion is lust, which in this system means not sexual desire but an appetite for intensity and for the full exertion of force; its virtue is innocence. Its wings are Seven and Nine. Under stress the system places Eight at Five, withdrawing and secretive; in growth it moves to Two, turning its force to the protection and care of others rather than to its own defence.
In the Hornevian groups, Riso and Hudson's second classification drawn from Karen Horney's three neurotic trends, Eight falls among the assertive types that move against others, alongside Three and Seven, its exertion of force being the most direct and outward expression of that strategy among the nine. Naranjo's instinctual subtypes cross each type with one of three biological drives, self-preservation, social and one-to-one (sexual). For Eight these give the self-preservation Survivalist, focused on satisfactory material security; the social Group Leader, whose force is turned toward friendship and shared causes; and the one-to-one Commander, whose intensity is expressed through possession and surrender in an intimate bond.