User blog comment:SayuriDarling/The Mark of Athena Official Discussion/@comment-4430596-20121014233445/@comment-3146930-20121015000513

I'm thinking that while falling into the portal to Tartarus (I think it is a portal anyway), once they pass into it, their decent will slow down and they'll only fall a couple feet, like a safety net. Or...Arachne will fall and hit a cliff or something, so the strand of silk will act like a bungee cord and prevent them from going splat.