Xin Ju
Later on, he went to Yan in the promise of fortune and from the moment he arrived in Yan, Geki Shin did little else but contemplate how to overcome the huge wall known as Gaku Ki. Geki Shin would follow Gaku Ki into as many battles as he could and recorded every detail he witnessed.
40 years prior to the story, both he and Gaku Ki pushed back encroaching Qi forces and won a huge victory for Yan.