User blog comment:Darkcloud1111/''The Mark of Athena'' Plot Holes/@comment-3146930-20121012184402/@comment-4531192-20121012190254

Well, all we know is, that particular demigod never reached Arachne. I mean, it was explicitly stated that Annabeth was the first ever child of Athena/Minerva to reach Arachne (and to survive all the traps that preceded meeting her). For all we know, that demigod may simply have gone mad during the period he was wandering in the Sea of Monster, trying to find his way to wherever he was going (if he even was sane enough to think about going somewhere).