Publisher's blurb: Crafted by a cabal of morphogenic sorcerers at the behest of their diabolical masters, these twin bridges are living entities of tendon and bone grown to a massive scale. Formed to provide passage over a lava flow in an infernal realm, these bridges provide twin choke points and are suited for defending against those that may try to cross. There are multiple variations that move the bridges to different, less hellish climates as well as some variations without the bridges.