Zarathustra e no Kaidan

is a Japanese light novel series written by Shinjiro Dobashi, with illustrations by Yukiko Horiguchi. The series began publication on November 10, 2007 by ASCII Media Works under their Dengeki Bunko publishing imprint.

Synopsis
"The existence that is worshiped as an ancient god and the heroes in history are the ones who controlled the pulse." An unknown existence- "Pulse".

Pulses parasitize the human psyche. It is said that when parasitized by a pulse, the intelligence and physical strength of the host human being will improve dramatically, and special power may be generated. The fate of Shunsuke Fukuhara, a high school student who was found to be infected with such a pulse, begins to move at once! The existence of a mysterious organization trying to control the pulse. And I met a girl who was also parasitized by Pulse.

What is waiting for Shunsuke's future ...!?