After the conclusion of The King of Iron Fist Tournament 4, an intense battle between father and son, Kazuya Mishima and Jin Kazama, took place at Hon-maru, located deep within the Mishima estate. Driven by a unflinching hate and resentment to destroy the father he has never known, Jin Kazama emerged as the victor. The eldest Mishima, Heihachi, enters the Hon-maru only to immediately gaze upon the unconscious body of his estranged and now defeated son, Kazuya. "What a pathetic wretch...You worthless coward!" So began the fated battle between Heihachi and Jin. Utterly consumed with the memory of Heihachi's vile betrayal 2 years early, Jin begins to manifest the Devil Blood he inherited from his father, Kazuya. Jin's black wings spread, Devil markings surface on his upper body. Heihachi, completely overwhelmed by Jin's inhuman strength and now defeated, can only prepare himself for his imminent death. On the verge of taking the life of his grandfather, Heihachi, Jin manages to momentarily regain control of himself. "Thank my mother, Jun Kazama, for your life." Jin said, before taking flight through the Hon-maru ceiling and into the night sky. The sounds of battle gave way to an eerie silence as Heihachi lay spread out on the ground contemplating the events that had just transpired. The silence was soon interrupted by what sounded like approaching aircraft. The roar of the aircraft increased and the sounds of something being ejected was heard in the distance. Unexpectedly, a group of "Jack" robots crashed through the Hon-Maru ceiling. At first, Heihachi suspected that Kazuya and his associates were responsible for the intrusion but realized that Kazuya was just as bewildered and stunned by the surprise attack. "Who sent you?! Why are you here?!" yells Heihachi as the first wave of Jacks approaches. With little choice left, Heihachi Mishima and Kazuya Mishima, father and son, form an unlikely alliance and together battle wave upon wave of Jacks, but reinforcements appear as fast as each Jack robot is disabled. Heihachi begins to tire and lose his breath. Kazuya, seizing the opportunity to rid himself of Heihachi once and for all, betrays him by mercilessly throwing him into the path of the oncoming army of Jack robots, and uses the opportunity to make his own escape from the now robot infested Hon-maru. A few moments after, Hon-maru is devastated by a titanic explosion. Close by, on a cliff top, the battle is watched by a man dressed in black. He raises his hand to his ear and speaks into his communication device. "Heihachi Mishima is dead..." At that very moment, a Jack robot attacks unexpectedly from behind but is sliced in half instantly by the mysterious man, as he disappears into the night. Hon-maru is completely destroyed, nothing but a raging inferno left in it's place. Once the aircraft disappear into the night, a pile of debris was blown apart as something emerged from the earth, unseen. The very next day, news of Heihachi Mishima's death spread rapidly across the globe. Most people believed that Heihachi's death would bring about the end of the Mishima Zaibatsu, but behind the scenes someone else had taken control, and business went on as usual. A month later, it was announced that the Mishima Zaibatsu will hold the King of Iron Fist Tournament 5.