These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Genius Bonus: The novel involves a cryptogram. A plot point is that a character deliberately errs in solving it, changing its meaning by changing two letters. The deception is not revealed until much later in the novel, but if the reader solves the cryptogram himself, he discovers it right away. This word is a character's name and he's the one who mistranslates the cryptogram so as not to implicate himself.
Nightmare Fuel: Imagine the scariest sea-creature lurking in the back of the mind of a marine biologist, and now give them the power to make it real.