Angelwatch was the new tower built by the Mechanists in Dayport. It apparently functioned as their administrative headquarters and public front, while their true base of operations, was at Soulforge Cathedral.
Karras arranged a ball at Angelwatch to gather money from the nobility, and to increase the prestige of the Mechanists in The City. His real intention, however, was to distribute Masked Servants to all of the nobles, a part of his plan to destroy all organic life in The City. Garrett infiltrated the tower when searching for information on the Cetus Project. 
Angelwatch consists of 6 floors, all with a different design. An elevator ran up the entire height of the structure. A staircase ran from the second to fifth floors.
The lowest level of Angelwatch was mainly a huge concourse and chapel. The ceiling was supported by huge beams of black marble. A door with odd properties led to the streets.
The second floor was quite cramped, with raw stone as walls and dingy lighting. Here there was a barracks, a small chapel, and a small laboratory area.
The library was the main feature of this area. A gear-gallery also adorned the third floor.
The fifth floor housed the guest rooms, a dining hall, and Karras' office.
The sixth floor was just one great ballroom, with a fountain in the middle, and a tile floor with wooden edging. Music in the ballroom was provided by one of the Worker Bots.
Angelwatch has a few oddities, such as the Castle Carlysle key working in one of the tower doors, the metal councorse door that is actually made of wood, and the fact that the tower has no bathrooms.