Cerebriliths spent their time cultivating their mental powers, usually acting alone or in groups of up to four, by hunting and killing mortal prey. They loved to kill intelligent beings and extract their brains, which they would examine in an effort to gain fresh insights into the powers of the mind. They only joined demon armies in specialist roles to meet specific purposes, such as to a slay a mortal psionicist or psionic creature. They could also use their powers of mental domination in larger schemes.