What I'm Excited for in House of Hades by Rick Riordan

Hey everyone!
It's almost the end of September and you know what that means... House of Hades! I cannot believe we're almost there! Anyways, here are some points I'm excited to see. Keep in mind that these may not happen, but since I read Mark of Athena, I have had a few ideas in mind. This will contain spoilers for the Heroes of Olympus series. If you haven't read them, let me say that you have to, for your own awesome.