De Acosta proved his skills in short order, earning a commendation from the Council of Lords for his efforts, as well as a gift of land within Palmyria, transforming him into a minor lord. Soon, he used that land to build his own research tower—a rival to Nachtmachen's Noche Torre. Even with his newfound success, the relationship between the two inventors initially remained friendly. Both sought to expand humanity's understanding and improve Manreia's wartime footing against the Grand Coven. Neither was particularly concerned with fame or notoriety, preferring to pursue science in its purist form. De Acosta followed his teacher's pattern, and used his newly built facility to train apprentices in the mastery of the steam engine, along with a broad range of other techniques.
Tragically, Von Nachtmachen's mental state began to rapidly deteriorate. There are many different tales of his madness and countless theories about its trigger. In essence, the once brilliant man isolated himself from the Council of Lords and all agents of Manreia's military.
Desperate for a solution to the war, the nation's leaders quickly turned to De Acosta to fulfill the role of master inventor for her armies. He reluctantly accepted the position, and began recruiting many additional apprentices—including a few who had fled from Noche Torre. Making full use of the rail system, he began to increase production, using less skilled apprentices to build the necessary components for many of his inventions. Though his production levels were never enough to completely stop the Witches, they proved a huge boon during the war.
The desperate and frantic construction provided a means of radically advancing Manreia's understanding of science and technology. To this day, it remains tremendously unclear just how many discoveries De Acosta and his students managed. As the Great War waned, desperate Manreian soldiers wielded many of the more thoroughly tested devices against the armies of the Grand Coven. However, it is generally accepted that only a tiny fraction of the creations ever made it through testing. Speculation suggests that there could be thousands of different inventions secreted away within De Acosta's tower. If this is true, only the inventor and his students know the full story of what devices exist and how they might be used.
Since the surrender, Manreia's Lord Warlock has imposed tremendous tithes upon De Acosta specifically. The ruler must first review every invention he creates before it can be sold to anyone else. Rumors abound that De Acosta's students have been smuggling creations out of his tower, so that underground groups can use them to fight against the Witches. The truth of this remains in dispute, and De Acosta publicly insists that any devices used against the Lord Warlock must have come from Noche Torre.