
Kyuuyaku Seisho Zokuhen is a Japanese non-fiction of 317,773 characters, with 10,018 unique words and 1,801 different kanji. Its difficulty rating on Jiten is hard, 3.9 out of 5. The full vocabulary list ranks all 10,018 words by how often they appear, and you can study them on Jiten or download them as an Anki deck.
Here are some of the words that appear most often in this media, as well as a sample of its rarer vocabulary.