The Molech's Enlightenment was a Cobra Destroyer in the Imperial Army during the Horus Heresy and took part in the Battle of Molech against the traitorous Warmaster and his forces. However, the Imperium's forces were defeated by the traitors and Molech's Enlightenment was the only loyalist ship to survive the battle. Despite this, though, the Destroyer's commander, Captain Sulaiman, returned to Molech and evacuated a small number of its population before then escaping into the Warp towards Terra. What followed was a nearly two year journey that was fraught with danger and pushed the Destroyer and its passengers to their limits. While Magos Cervari was able to barely keep Molech's Enlightenment functional, its supplies were limited and a number of its passengers passed away as it neared Terra.
Just before it entered the Sol System, though, Captain Sulaiman began to argue with the Molech survivor Alivia Sureka about how they should enter the System. Sureka argued that due to the Warmaster's treachery the Sol System would be heavily defended by the Imperium and its forces would destroy any ship that entered it from the Warp unannounced. She suggested that they should use a less known Mandeville Point, which would give them time to safely contact the Imperium, rather than the well known Elysian Gate, as Sulaiman had planned, which was closer to Terra. The Captain disregarded her suggestion, though, as he viewed her as a civilian, albeit one who had become well regarded and called a Saint by most aboard the Destroyer, and he refused to have his ship enter the Sol System like an intruder. He then ordered Molech's Enlightenment to exit the Warp through the Elysian Gate - and in doing so nearly had it destroyed, as the Imperium's forces near the Gate immediately fired upon it.
This forced Sureka to intervene and she asked Sulaiman to evade and keep them alive long enough for her to ask for help. The confused Captain agreed, not knowing that Sureka was in fact a Perpetual, who had been in psychic contact with one of her brethren since they neared the Sol System. Known as John Grammaticus, he had repeatedly offered to help the Molech's Enlightenment safely reach Terra, if Sureka would tell him where the missing Perpetual Oll Persson was. Sureka had refused to help him before, due to their troubled history together and not knowing where Persson was, but with the Molech's Enlightenment facing certain destruction, she contacted John and agreed to his deal. With her aid secured, John used his influence with the Imperium, to call off the attack on the Molech's Enlightenment, which had been mere moments from being destroyed. The Destroyer was then escorted to Terra by the Battleship Cardinal Boras, where the survivors of Molech safely disembarked.