User blog comment:SirMoodletonofCanadia/What do you think would happen if Percy had stayed with Calypso??????/@comment-3146930-20110112052000/@comment-3146930-20111212011343

So what would stop Hades from popping out of the ground after or before Typhon crossed the river? Poseidon only waited because he had the elemental advantage in the river. Hades however could create a direct link to Tartarus. Seriously, just read the story, I promise it will make sense