Meme Acknowledgement: Jason's memetic reputation for being knocked out a lot is referenced in the chapter title "Hearthstone Passes Out More Than Jason Grace (Even Though I have No Idea Who That Is).
There was a small commercial for "Ship of the Dead", where a group of vikings argued over the correct way to pronounce "falafel", and whether or not it had any nutrition. One viking finally ends the conversation by stating that a great warrior named Magnus loved the food and ate it often, before holding up the book.