Epistolary Menoloth, the Lost One

905.M41 While searching for an image he saw in a vision, Chief Librarian Menoloth disappears into the Maelstrom with a small bodyguard. They are presumed lost in the warp, it is a grievous blow to the Chapter.

997.M41 Epistolary Menoloth, now known as the Lost One, returns from the Maelstrom with the daemon blade Walach. None of his bodyguard remain. After extensive testing it is determined Menoloth remains pure of heart, so he takes command of the newly formed Strike Force Ostro, composed mostly of Brothers whose recruitment was censured by the High Lords.

998.M41 Strike Force Ostro encounters Dark Eldar Covens on the Eastern Fringe as the Lamenters begin to Crusade out past the light of the Astronomicon.