User blog comment:SayuriDarling/Full first chapter of The Mark of Athena/@comment-4566556-20120614082311/@comment-3146930-20120614222110

Since when does Percy make Earthquakes? I mean he has shown to be able to cause fissures when he stabs Riptide into the ground, but no one is really sure if that is Percy's power, Riptide's power, combined power, or if Percy uses his water powers to force water into the spot he stabs, causing whatever he stabs into to make fissures