Borderline

Borderline (, Kyoukai-sen) is the basic ability of all shinki. It cannot be used by gods, humans, or loose spirits.

Casting Sequence
It is performed by extending the index and middle fingers into a lance and drawing a line between "self" and "other". The technique is typically accompanied by shouting "A line!" (, issen). The barrier it creates cannot be crossed by phantoms.

Applications

 * Boundary: The main advantage of a borderline is protection from phantoms, which cannot cross through them under normal circumstances.
 * Mental borderlines: The principle of forming a borderline is also extended to a shinki's vessel form. Divine weapons who are skilled with borderlines are able to precisely determine what they do and do not want to damage. By mentally drawing a borderline between the Near Shore and Far Shore, gods and shinki are able to avoid causing destruction the living realm during battles. However, this skill does not always come naturally. For example, Yukine often failed to draw mental borderlines at first, despite having a natural talent for physical borderlines. Similarly, Yugiha is not well-practiced in maintaining mental borderlines without Kazuma's help, and attacks with too much power when he isn't present.
 * Purgatory (, goku): Three shinki can entrap an opponent by each creating borderlines which intersect in the shape of a triangle.
 * Ablution (, misogi): Three shinki perform borderlines to create a Purgatory, entrapping the shinki who must go through the purification ritual.
 * Lance (, hoko): By drawing the line into the air rather than the ground, a borderline can be used as an offensive strike against an opponent. Against other shinki, this has been shown to be powerful enough to knock a person back and draw blood. Against phantoms, it is enough to exterminate them.
 * Shield (, tate): A shinki can block a lance by performing another borderline to intercept it.

Restrictions

 * The effectiveness of a borderline is determined by mental fortitude and the current power imbalance between the caster and target.
 * Borderlines alone are not enough to kill a god. However, they can be used to entrap a god.