Alas, Poor Villain: His backstory in Tekken 7 shows that he was a simple man happy to spend his days training and was also a happily married man.Parental Abandonment is actually a blessing when it comes to being Heihachi's child!

Notably his second son, Lars, who was NOT raised by Heihachi, turned out to be a pretty good guy.Later on he ropes his son and grandson into being future subjects for his research. Grandson? More like live bait to attract an ancient monster that feeds off fighting skill! Did he screw up your plan by killing the beast? Bullet between the eyes. He also extends his abuse over the generations.Then he tries to kill them when the ungrateful brats don't appreciate all he's done for them. While his own dad was practically a saint ( Demonic Possession aside), Heihachi thinks chucking your son off a cliff or adopting another son solely to foment a sibling rivalry are sound parenting skills.He now continues the war against G Corporation and Kazuya, hoping to engage in one final battle to decide their fate. With Jin out of commission, but still alive unbeknownst to anyone, Heihachi once again seized control of the Zaibatsu. This pays off when, in the end, Jin sacrifices himself to stop the being known as Azazel and Kazuya leaves out of boredom. As Lars leaves, he surmises that Lars will end up doing his work for him, and continues to lay low. During Scenario Campaign, his plans to take back the Zaibatsu are interrupted in their early stages when Lars shows up and confronts him, revealing that he is Heihachi's son from an affair he had in the Netherlands.

Heihachi survived, being no ordinary man, but was rendered unconscious for the entirety of the 5th tournament while Jin took over the Zaibatsu. Jin foils his plan, then he gets ambushed by Jack robots, then Kazuya betrays him and the Jack robots self-destruct on him after dogpiling him. Later he found out that Kazuya was still alive, and hosts the 4th tournament to lure his descendants for his plans. Once Jin beats Ogre, Heihachi betrays Jin by shooting him in the head, only to be smacked back by Devil Jin and thrown out of Ogre's temple through a wall. When he's approached by his grandson Jin Kazama, who wants to avenge his mother's death at the hands of Ogre, Heihachi uses him to lure Ogre out. For years, Heihachi built up a good reputation with his Zaibatsu while hiding his own ambitions.

Kazuya tekken 1