A Stenza warrior wears his conquests.
The act of taking and wearing a trophy dates back almost to the dawn of the practice of hunting among the Stenza. It served, and still serves, several key social functions: bragging rights, preventing others from lying about who killed what, and attracting mates. It has taken many forms over the years, from something resembling jewelry (still seen in An'o (Dance)), to attaching pieces of horn to various body parts. Trophies from a kill were always distinct from the pieces of a carcass used for tools or clothing (such as hide or shoulder-blades), and when the latter was phased out due to technological advancement, the trophy became a sort of symbolic link back to the ancestors. Due to the development of the Uniform, the number of places one could wear their trophies was strictly limited, and this trickled down into society at large until it became common to make use of real estate on one's face.
NSFWIt is generally frowned upon, but not strictly taboo, for civilians to perform this practice with specific kills (animals killed for food are fair game for everyone, however). It is taboo, however, for this to be done to corpses belonging to fellow Stenza or those killed for crimes against pups.
When a Stenza soldier kills an enemy combatant (or periodically an enemy civilian), he or she kneels before the body, breaking apart the jaw, if applicable, and pulling out a tooth, fang, or mandible. Other options are claws and certain venom sacs, depending on the species the enemy belonged to in life. The trophy is then implanted into the skin of the face, for purposes of intimidation or to show off (or a blend of both).