The giants who capture Herio and Philpott in Doom are described below as they are in Doom's Glossary and in Heart of the Staff, the Complete Appendix.
Giants - Gigantopithecus blacki R., also known as howlers or howlies or tall men, gigantic secretive nocturnal hominids that walk upright and live just below the tree line of the Sunset Mountains and in other isolated areas of the Northern Continent. Males range from eight to ten feet tall and can weigh more than eleven hundred pounds. Females range from seven to eight and a half feet tall and weigh half that of the males. Both sexes are entirely covered with a shaggy, nearly black dark brown hair, except for the palms of their hands, the soles of their feet and the forehead and cheeks of the males, and the entire faces of females. The irises of their eyes can be brown or bright blue, whilst the whites of their eyes are black. Their faces are broad and flat in a manner suggestive of the orangutan. Their jaws are V-shaped like those of humans, allowing a bipedal upright carriage of the skull, setting them apart from the great apes. Their molars are far heavier in proportion than those of humans, making them able to masticate whole nuts and other roughage impossible for humans to chew. Their jaw muscles cover the sides of their heads and are anchored to a prominent boney sagittal crest running along the top of their skulls, rather than merely being anchored around the temples as in modern humans. Not only do they walk fully erect in the manner that we do, but their leg bones are similarly proportioned to ours and their toes point forward and are not used for grasping as in the great apes. Additionally, their hands have the prominent thumbs of human hands, further setting them apart from the apes. And whilst their arms are enough longer in proportion to their bodies than humans' to suggest those of the great apes, they are not long enough to facilitate their knuckle walking quad-ambulation. Both sexes produce an intensely musky pungence that hangs in the air after their passage. It is claimed that the sex of the individual who released a given odor can be reliably determined by human observers who have been around them long enough to become familiar with the creatures. It is not known whether they have voluntary control over the scent. The females ovulate every twenty-eight days like humans rather than having a seasonal estrus as do the apes, and they form life long pair bonds. It is evident that the young are dependent upon their parents throughout their development and take a long time to reach maturity, though just what that length of time happens to be is unknown. They seem not to have a verbal language, though they utter groans and much grunting in close proximity to other individuals, and they make loud long wails (described as hair raising) which can be heard for miles on still nights. What they do have instead of speech is an astonishing and articulate system of sign language, able to ask questions and to convey detail about specific conditions and entities removed in space and time. They also scratch hieroglyphs and crude drawings in the dirt and on rocks and tree trunks. Though they never have been known to shape stone tools, they are quite handy at using un-worked stones and well chosen sticks as tools. They have never been known to use fire. However, they have the incessant habit of stripping fibers from all sorts of plants and scattering about occasional twists of them where they have been. They also tie up bundles of such fibers into pallets and effigies which observers captured by them have seen being used as dolls for the female young.
Carol Marrs Phipps & Tom Phipps