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Rupture (爆裂) is a magic designed solely for military purposes. Rupture is a Dispersal Type spell, which evaporates all liquids within an object. In the case of living organisms, body fluids will evaporate and the body will explode with its red blood cells scattering outwards like a crimson flower blooming in the spring. 
Since nearly all machines have a fluid of some kind, such as lubricants, coolants, hydraulic or battery fluids or liquid fuel, they will instantly be destroyed by explosion or simply stop working. This is the perfect magic for both anti-personnel and anti-armor combat.
Its weakness is that it doesn't work against targets that do not have any fluids in them. Rupture cast by Ichijou Masaki was unable to counteract phantom troops (which had no fluid inside it) created by Ancient Magic. It also requires the location of the individual target rather than working in a wide area.
It's said that jumping into water in the face of Ichijou family rupture is the same as charging into a mountain of bombs.