Yahru was an elementless matoran who was trained in the fighting style of Mata Taekworu Zhex by Seihu , along with his former friend Shinorax. He went across the island of Mata Nui to learn more about all the Matoran, Turaga and Toa; as well as gain skills that were unique from each of the 6 villages. In other words, he was a secret Chronicler. He was sent to Voya Nui by Turaga Seihu to help the Toa Inika fight the Piraka. He follows a code of honor, therefore his personality is calm, honorable, and noble. Sometimes, he doubts his own abilities and sometimes uses training to hide his insecurities about his skills.
Yahru also has a very balanced fighting style in both skill and strength. Being that he was trained by Toa Seihu the longest, he is the most seasoned out of the team.