Halo: Silentium

Halo: Silentium is the third novel in The Forerunner Saga by Greg Bear, was released on March 19, 2013.

Plot
In the last years of the Forerunner empire, chaos rules. The Flood has arrived in force, aided by an unexpected ally. Internal strife within the ecumene has desperately weakened Forerunner defenses.

Too little, too late, the legal rate of Juridicals is only now investigating possible crimes by the Master Builder and others. Evidence-gathering agents known collectively as the Catalogs have been dispatched to collect testimony from the Librarian and both Didacts: the Ur-Didact, treacherously abandoned in a Flood-infested system, and the Bornstellar Didact, who accompanies the Librarian as she preserves specimens against the dire possibility of Halo extermination.

Facing the imminent collapse of their civilization, the Librarian and the Ur-Didact reveal what they know about the relationship between the long-vanished Precursors and the Flood.

The Precursors created many technological species, including humanity and the Forerunners. But the roots of the Flood may be found in an act of enormous barbarity, carried out beyond our galaxy ten million years before...

Because of that barbarism, a greater evil looms. Only the Ur-Didact and the Librarian—husband and wife pushed into desperate conflict—hold the keys to a solution.

Facing the consequences of a mythic tragedy, one of them must now commit the greatest atrocity of all time—to prevent an insane evil from dominating the entire universe.

Trivia

 * The story is presented through many the eyes of many characters, incudling the Librarian, both Didacts, Catalog and the Master Builder.
 * 343 added a Glyph code to celebrate the release of Silentium
 * Also that the video that comes, with the entry of the codes, is the exact one 343 deleted from Halo: Combat Evolved Anniversary, that was noted as the "???" 12th Terminal with this expression;
 * "For decades we have battled an alien enemy we do not understand. Unprovoked, they brought our civilization to it's knees, and forced us into hiding".
 * The next day the video was replaced with an audio video narrated by Greg Bear, and which tells the story of Riser after the Halo Array was activated by the Bornstellar-Didact.