I'm really glad that all the books already published years ago, so I don't need to bang my head on the wall for that little CLIFF HANGER!! 
 I personally love this book so much than The Lost Hero. I suppose the plot more interesting and the characters' characterization improve. I think Rick Riordan did excellent in writing Percy Jackson spin-off with incredible characters' development. I wish that he keeps writing about them until I'm in old age. If it's possible, I think there's no problem to keep elaborating the story :). 
 And also the writing style. Oh, my god! It's magnificent. I can imagine how the story happens inside my head exactly like a movie. Particularly, the battle part. No doubt whatsoever about that. 
 Highly Recommend to all demigods.