Vulung is the hundred-pacer viper (Deinagkistrodon acutus) revered by the Paiwan as their senior ancestor and guardian numen, and as the special patron of the aristocratic mamazangiljan lineages. In the widely told origin tradition, the sun deposits its eggs on the sacred Mount Kavulungan (Mount Dawu / Beidawu); from these the hundred-pacer and the first noble Paiwan ancestors hatch as siblings, making the snake and the chiefly houses literal kin. The viper's distinctive diamond or lozenge markings became the single most important motif of Paiwan visual culture: rows of rhombuses representing the snake's back adorn the carved house-posts (qeluz), lintels, headdresses and ceremonial garments of noble houses, and the right to display the motif was historically restricted to the aristocracy. The Paiwan hold that the souls of the dead return to Kavulungan to be reunited with the ancestral snake. Rather than an individuated anthropomorphic god, Vulung is best understood as a sacred ancestral being and lineage-numen, central to the snake-ancestor cult that underpins Paiwan social hierarchy.