The common Thargoid warrior is a dark chitin-covered insect measuring just over 7 feet / 2 metres in height. They have six limbs, two of which are dedicated walking limbs (legs). The remaining four limbs have jointed hands each possessing three digits, one of which is an opposable thumb.
The head is a triangular ovoid in shape, with prominent faceted eyes mounted to the front. In general, the overall impression is similar to that of a praying mantis. There are two short antennae that protrude from the top of the head. The mouth is on the underside of the front point of the triangular head, and is relatively small. It is surrounded to two strong mandibles. The neck is very short but thick and sturdy, and can rotate 60 degrees.
The body of a Thargoid is segmented into two distinct sections. The upper segment is approximately egg-shaped with a slight distension at the upper end just below the junction to the neck and head; this is where the upper limbs join the body. The lower segment is a tapered oval that arcs slightly towards the rear and forms a rounded point. The junction of these two segments is a heavily muscled narrow waist which the Thargoid can twist to approximately 100 degrees.
The lower four limbs are attached to the lower body segment. The lowest pair, or the traditional legs, are attached just above the point where the segment begins to bend rearwards. These legs have knee joints and ankle joint, and are terminated with clawed appendages. The ankles allow the Thargoid to use the lowest part of the limb as feet, providing stability and agility when standing erect. These legs are also double jointed at the knees. The middle pair of limbs are primarily used as manipulating limbs, but are also seen as propelling limbs when a Thargoid is running. These limbs are jointed at elbow and wrist, and end in clawed hands. There are four digits, including an opposable thumb, and these are clawed. The claws are short and horny. These legs are usually held folded against the front of the body.
The upper limbs are dedicated manipulatory limbs. These are jointed at the elbows and wrists. The elbow is jointed to the rear, similar to human arms. The hands end in four clawed digits, one of which is an opposable thumb. These digits are more flexible and agile than the ones on the middle limbs.
Thargoids can walk erect on the hind legs, but have been seen to drop to four legs when running, using the middle limbs in addition to the rear legs.
Not much is known about the internal workings of Thargoid anatomy. Dissection of specimens have revealed the presence of several organs analogous to humans, as well as some that are common in insectoid races. Oresrian medical personnel have verified the presence of respiratory and circulatory organs as well as the digestive organs and system. They have also identified several glands such as excretory, pheromonal and communication glands (most insectoid communication is a hybrid of aural and pheromone methods). The fabled 'fear glands' thought to be removed from Thargoid warriors are thought to be located in the upper thorax, where scar tissue has been found. No notable reproductive organs have been found in specimens, leading scientists to theorise that there must be a separate phenotype of Thargoid that is responsible for the reproductive act.
