The receptacle of the first words and the second receptacle of the Moment of All Creation. The SourceBook is an item created with the multiverse but exists within one universe at a time. The SourceBook would later be manipulated by a man named Doctor Scott to hold and contain all his knowledge, most of which was given to him by a being known as the Watcher after the end of the Post-Convergence Multiverse. This book remains the only source of history for the universes that came before as, after Doctor Scott's death, none remain whom experienced them. After Dr. Scott's death, the book was recovered by agents of the The Terminus and brought back to the Doom-Coil.
A Conversation with Rā’s al Ghūl: "We could fight Ajull, I feel you are man enough to face your better, we could end one another but I hardly think that is necessary. You've come looking for something, what is it?" Dawnguard then admitted he was looking for the SourceBook "You don't want the SourceBook, you want what he wrote down, I can give it to you. Not the breadth of it, no one can do that but the book but I can tell you the truth of it. Doctor Scott wanted to tell you everything he knew and my legion gathered much of it from the journals he used to prepare. After eighteen or nineteen billion years of existence, he'd gone quite mad but he'd tracked the SourceBook from the start and took the time to prepare himself. He knew that he could trap the breadth of his knowledge in the book in just a moment; so, he prepare to trap only what was needed. In his journals, he began at the beginning. In the last moments of his life in the universe before the Crisis, a flake of Scott was preserved by the Watcher whom could effect all the universe before his death at the very start of it and with that ability he preserved Doctor Scott in the next universe. Recreated, Doctor Scott wrote in his journal that he was born sometime near the moment of creation but that it would take him several hundred thousand years to gain the knowledge that he needed to find the SourceBook. For millions of years he searched. For a hundred million he wandered but eventually he found out that the book was lost in the Doom-Coil of The Terminus. When he entered he had no way of knowing how long he would remain. It took him the span of billions of years to get the book and get out and it took him another billion to cure himself of the madness from trying to read it. Before he knew it, time had come around again. He fell back into his old ways, repeating history for the sake of recreating it, once again joining the Society, thousands of years went by as he just searched for the answers. In the end he wrote of the Guardians of Oa and their conspiracy to hide Perpetua and Zenric. In the end he wrote that the Titan's war could forever alter life and the cycle of the universes before him. In the end he wrote that his passage of knowledge would preserve all as a way to preserve all that will be. Doctor Scott was a hero to the universe, even to me, and as heroes do; he played out his life and at some point before his end, he gave everything he could to the book." Rā’s continued, "what he wrote of, that you want to know most chiefly, was that it was he whom planned the death of your doppelgangers. Doctor Scott traded a favor with Azgenerath, a New God, to empower your dragon's flames to sunder those heroes permanently. He wrote that he would do so, so that his magic would pull you into the new universe and into a collapsing timeline in the future that he was sure you would come back and collapse. You see, your enemy all along was your greatest ally." In conclusion he stated, "there is more information to be found in the Book of Nihilhor, I'm sure you have it."