This is a reading guide to help you choose from both the “main” Gunmetal Olympus books by Maria Ying and the “expanded universe” by other writers.
Main books
These are the titles by Maria Ying. They contextualize most of the Gunmetal Olympus body of work.
- The Hades Calculus (novel)
- Memory of Olympus (collection of side- and back-stories)
- The Persephone Effect (novel)
Companion books
- The Zeus Constant by Callisto Khan (to be read with The Hades Calculus; mostly canonical)
- Flower of the Underworld by Cirice Gray (to be read with The Hades Calculus; canonical)
- House of the Underworld by Cirice Gray (to be read with The Persephone Effect; canonical)

Standalones
These can be read completely independent from the rest, including Maria Ying books.
- Pink Diamond and Keeping the Peace by Tris Husband (both starring the same protagonist)
- A Drone’s Domain by Luna Selvin
Alternate universes/what-if
- In Her Garden by Abigail Gloom (bad end)
- The Grafting of Persephone by Autumn Wolff (bad end)
- Reap and Sow by SpecterOC (very evil AU)
- Cosysick by Jemma Topaz (various types of AU)
- The Dee Dee Calculus by Bailey Saxon (AU, both funny and evil)
Other fanfic not yet compiled/published as books can be found on AO3.