A modern sanda champion starves to death beneath a bridge in Amegakure, his corpse washed by torrential rain for three days.
The championship trophy clutched in his hands before he died suddenly bears blood-red markings, devouring the chakra of three Rain ninjas.
When his consciousness awakens, he finds himself in a pure white space, where he sees a sign bearing the name "Zero-Degree Martial Arts Academy."
