The fusion of a human and hunting spider. Vertigo can cling to any surface, scurrying monkey-like up the slickest walls and even crawling upside-down from ceilings. They produce webbing from both the anus and mouth, which they use to bind prey. Small birds are their favorite food, easily snared in the dangling globs of silk they hang from rooftops and tree branches. Their bite causes spasms that result in uncontrollable "dancing" before the victim loses consciousness. Vertigo are amused by normal spiders, and enjoy toying with them.

   A Vertigo's size and coloration can vary according to the spider used in bio-fusion, but their unifying human element allows them to freely interbreed and produce a seemingly infinite array of mixed offspring. The largest known colony of feral Vertigo, however, are a uniform inky black with gleaming white faces. This unusual population breeds only with its own and demonstrates violent xenophobia. Any young that differ even slightly in coloration are immediately slaughtered along with the mother who hatched them, their bodies shunned as food and added to the towering heap of corpses at the mouth of their subterranean lair. For miles around this rotting mountain, the ground softly vibrates with the underground footfalls of millions.