OVA
Description
Heihachi Mishima orchestrates the King of Iron Fist Tournament from his private island. His past reveals defining cruelty toward his son Kazuya, whom Heihachi cold-bloodedly threw from a cliff as a child, citing survival of the fittest—comparing it to lions testing cubs—due to perceiving Kazuya's weakness.

Later, Heihachi adopted Lee Chaolan as heir to the Mishima Zaibatsu. He sanctioned assassination attempts on Kazuya, hiring fighters Nina and Anna Williams to eliminate his biological son, part of his broader agenda to consolidate power and remove threats.

Heihachi initiated the tournament partly to lure Kazuya into confrontation, anticipating his vengeance. Sequestered in the central tower, he monitored proceedings via subordinate Lee Chaolan, who managed operations and reported on the "R-experiment"—creating invisible, dinosaur-like bio-weapons for global deployment. Heihachi grew impatient for Kazuya's arrival.

Heihachi demonstrated formidable combat prowess during the event, intercepting competitor Michelle Chang's thrown axe with his teeth and effortlessly destroying it as intimidation.

His relationship with Lee Chaolan shattered. Heihachi physically removed Lee from a confrontation with Kazuya at the tower entrance, openly dismissing him as "worthless" and belittling his bio-weapon project despite its potential.

Heihachi confronted Kazuya directly at the climax. Their battle unfolded amidst Lee activating the island's self-destruct sequence. Heihachi dominated Kazuya until Jun Kazama intervened, challenging his motives. Heihachi articulated his nihilistic worldview, declaring humanity's inherent violence, masked by justifications, necessitated global destruction for a new beginning.

After Kazuya spared him, Heihachi launched a surprise attack against both Kazuya and Jun near flowing lava within the deteriorating complex. Surviving the island's destruction, Heihachi escaped via personal jet, departing with a final defiant smirk.

His philosophy consistently centered on strength through conflict and rejecting perceived human weakness. His actions reflected imposing his will by force, extending to his vision of reshaping the world by eliminating existing structures.