Also known as: 三島平八
A central antagonist in the Tekken series, with the main story revolving around his quest for power and revenge. He was also famous for his incredible resilience.
Years before the first Tekken tournament, Heihachi took over the title of Mishima Zaibatsu CEO from his father Jinpachi and threw his son Kazuya off a cliff.
He hosted the first Tekken tournament to see if any fighter was worthy enough to beat him. It seemed that no one was able to meet the criteria until his son Kazuya, thought dead, confronted him. In an ironic twist, Kazuya defeated Heihachi and threw him off the same cliff, making him the new CEO of the Mishima Zaibatsu.
In the subsequent releases, Heihachi was often seen being killed by several powerful opponents, only to survive and return in the next game to exact revenge. He was (seemingly) being killed off for good in Tekken 7 after being weakened by Akuma (Street Fighter)'s Shun Goku Satsu & thrown into lava by Kazuya. However, he would later made his unexpected return in Tekken 8.