I remember this one being my favorite the first time I read the books, but now I'm not quite sure why.
I kind of like that Rachel Elizabeth Dare shows back up. In The Titan's Curse it kind of felt like someone had won a contest to get a character named after them... her appearance was so random. So it's nice that she actually has a part to play. (Like I said in my last review, I completely forgot so much of this series. Whole subplots didn't stick with me at all.)
There was another annoying cliche in the book of women who are naturally beautiful vs women who wear "too much makeup" (see Calypso vs The Sphinx). This idea crops up in a few of Riordan's books and I'm not a fan. It's an annoying, cliched message that just feels like lazy writing.
The use of cripple comes up again in this book. In this case Hephaestus is using it to describe himself, so I'm not quite sure what to make of that. Possibly still ableist usage of the term.
And can we please just kill the description "almond eyes" with fire? Even for non-Asian characters.
Overall, the pacing felt a little strange at times, but the story is good, raising the stakes and leading into the finale.