heptalogy

compound literary or narrative work that is made up of seven distinct works; compound work that is made up of seven distinct works

Seven Military Classics
Star of the Guardians tetralogy
Septimus Heap
Harry Potter
The Death Gate Cycle
Apprentice Adept
The Birds of Australia
The Saga of Seven Suns
The Tales of Alvin Maker
The Gospel as Revealed to Me
Percy Jackson & the Olympians
Molly Moon's Incredible Book of Hypnotism
Licht
The Chronicles of Narnia
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