This chapter's epigraph is from a famous poem by the English poet William Butler Yeats. It's about a man who's willing to fight his master against him. In this case, it's the mummy. The poem's title refers to the fact that the mummy is at the "yin" rank, which is the highest level of cultivation. In other words, the mummy's at the top of the totem pole, which means that he's strong enough to defeat the master of his own rank. This is the first time we've heard of this kind of thing, so we're not sure what to make of it. The master of the poem asks which one of his students is willing to face off with the mummy . Which one? Well, it turns out that the old man is good at teaching his students. The old man tells the students that the yin rank is for those who are strongest in the core, or meditation realm. The other students are at the zan, or disaster, or spirit, or devastation, or the other levels of cultivation, which are the highest levels of the heavenly realm. So, if you're at