Gun Sighted can be obtained by having Billy the Kid reach Bond level 10.
Gun Sighted is Billy the Kid's max bond CE and an exclusive to Billy the Kid.
Rashoumon event (Ibaraki Douji event)
Murder at the Kogetsukan
Inheritance of Glory
Ryougi Shiki (Saber)
Merlin
Jeanne d’Arc (Alter)
Altria Pendragon
Altera (Attila)
Altria Pendragon (Lancer)
Dragon Fang
Ereshkigal
Arthur Pendragon(Prototype)
Gorgon
Black Holy Grail (The Black Grail)