Canon Foreigner: This chapter features a cameo of Big Boobed Bertha and Camicazi from the books.
Hypocrite: Astrid realizes that she's going against her own beliefs by not only breaking into the chief's house to steal the journal of someone she dislikes, but by using said journal to form an alliance with a dragon. She justifies it as being for her people, and planning to kill the creature she tames to prove she's still as ruthless as ever.
Mythology Gag: The chapter includes a rewritten version of "We Don't Talk About Bruno" where various Berk vikings sing about Hiccup.
This Is Gonna Suck: In order to find the nest and free Berk from the dragons forever, Astrid realizes that she'll have to work with a dragon...aka, the one creature she hates more than anything else.
Title Drop: One of the lyrics to "We Don't Talk About Hiccup" is "How'd you train a dragon, Hiccup?"
