The Church of Illumination, located inside the Castle of the Angel, symbolizes the determination, ingenuity, and boldness of the 16th-century Illuminati scientists, who valued scientific illumination above all else. They disguised their meeting place in a Vatican building and laid out a series of clues that lead the prospective Illuminatus through Rome. Deciphering the clues require knowledge from various fields, including art, Catholic religion, and pagan religions, which alludes to the breadth of knowledge valued by the Illuminati.

This Church’s location near the Vatican was a brazen choice given the murder of four Illuminati scientists. Its location is an open secret, in plain sight of Vatican headquarters, establishing the perseverance of science even in the face of theocratic oppression. The organization hid its lair at the end of a complex map that requires ingenuity and curiosity to solve, illustrating their preference for these qualities above all others.

Antimatter symbolizes the pinnacle of scientific achievement. It can be harnessed for immense power and lends itself to the support of both scientific and religious theories, but it also has the potential to cause mass destruction. The Camerlengo warns against unbridled progress without considering moral implications. To prove his point—and to symbolize the triumph of religion over science—he hides the canister of antimatter underneath the Vatican and then successfully removes it.