User blog comment:Xilinoc/Ch. 645 - Don't Chase a Shadow/@comment-24769684-20151001103541/@comment-24546844-20151001141910

X-axis is an horizontal line in a plane, it makes sense if we consider the barrel as part of said line. Exorcist on the other hand makes no sense.

That opens the question: if his power is to pierce everything on a line, does he need the gun to do it or can he just use his ability with his fingers or his eyes?