Distortion of the Laws of the World

The Distortion of the Laws of the World is an event that occurs before the start of the Angel Fall Arc, quite possibly years before the start of the series. According to Fiamma of the Right, it is an event that occurred unnoticed as magic still works even with the distortion.

Principles
It is of yet unknown what caused the distortion, though its effects are distinctive. According to Fiamma of the Right, the distortion created holes that allowed an event such as Angel Fall to occur. As the name indicates, the distortion effects the laws of the world, e.g. the four elements of Earth, Fire, Wind, and Water. The elemental alignment of the four Archangels; Uriel, Raphael, Gabriel and Michael, switched, severely weakening them, and most notably allowed them to bypass the name that God has given them.

It is unknown what other laws have been distorted due to this event, but the occurence of the Distortion might be linked with the founding of Academy City and the creation of the Imaginary Number District, although the issue hasn't been raised.

Angel Fall Arc
The first hint of the Distortion appears during the activation of Angel Fall, when Archangel Gabriel under the form of Sasha Kreutzev takes on the name of Archangel Michael as Misha Kreutzev.

World War III Arc
Fiamma of the Right addresses the event directly during his battle with Vento of the Front, where he states how the angel that Vento of the Front is aligned to — Archangel Uriel — normally has the attributes of Earth and not the Wind. He even goes on to say that this is a serious matter that requires immediate attention, hinting that the distortion could've gotten out of hand.

Fiamma created the Star of Bethlehem for many purposes, one of them was to restore the elemental balance so his Holy Right would be perfectly aligned with Archangel Michael. The Distortion is finally undone by the use of Christian symbolism and the Star of Bethlehem.