The bombing of Geil is the first recorded instance in Mersian history of the use of nuclear weapons. The bombing took place during the Adenian-Tethish War.

Aden dropped flyers in Tethish over the city for weeks beforehand, demanding the evacuation of civilians from the city and promising the destruction by “All-consuming Fire Hitherto Unseen” of anyone who remained in the city. The city was gradually evacuated over the following weeks, and was nearly empty at the time of the bombing, save for those who did not take the warning seriously, and for members of the armed forces who were called in to defend the city from the bomber. The bomber, a Lerontz B-26 Aircastle bomber christened “Cerulean Sunset”, was a new design which flew at an altitude of 7 miles, far outside the known range of anti-aircraft magic.

The day of the bombing was cloudy, and an escort of fighter planes flew alongside the bomber as an extra security measure. Two fighter planes dropped below cloud cover about five miles north of Geil in order to verify the location of the target. One of these planes was flown by then-pilot Vincent Thompson, and had one of its engines shot out by Geil's defensive mages. Vincent could not climb back to the cruising altitude with the subsequently reduced engine power and was forced to make an emergency crash landing two dozen miles south of Geil, taking heavy fire from Geil's mages all the while. The other plane verified the coordinates of the city and climbed back above cloud cover.