Light Bringer
Eight months after the fall of Mercury. Darrow looks for a way to be somebody other than the Reaper, while across the system the boy who was meant to be his opposite becomes his perfect successor.
Plot in detail
Darrow: hiding after Mercury's fall, he sails with Cassius and Aurae to find Sevro on Venus, loses a duel to Apollonius, and is rescued when Sevro bombs the dockyards. Below Europa the The Daughters put him on trial and Sevro gets him spared. He then publicly beats Volsung Fá in a duel and, before the Moon Lords, apologises for destroying Ganymede's dockyards.
Lysander: hailed as Mercury's saviour, he renames the Morning Star the Lightbringer and defies Atalantia, who kills Glirastes. He attacks Phobos, survives a poisoning arranged by Atlas through Rhone, and with Cassius kills them both. When Cassius tries to seize Eidmi, Lysander kills him, skips the summit, devastates Io, and flees to the Core.
Lyria and Volga: Matteo rescues Lyria and removes Figment's parasite at the cost of her memories. She stows away on Quicksilver's generation ship and reaches Volga, who cannot kill her when Fá orders it. After the duel Volga kills Fá and becomes Queen of the Obsidians.