JACK-5 finished collecting fight data at The King of Iron Fist Tournament 5 and headed back to the G Corporation's laboratories. Jane used this data in her research to develop more sophisticated combat algorithms for him.

While G Corporation was at war with the Mishima Zaibatsu, mass-produced JACK units were deployed around the world. Unconfirmed reports claimed the Mishima Zaibatsu had begun manufacturing a copy of the JACK unit designed for large-scale massacre. Jane was angry that JACK was being imitated, so she sent in the more sophisticated model JACK-6 in order to investigate the truth behind the rumors.

A nass-produced fighting machine, JACK-5 uses its robotic brute strength to pummel opponents into a messy pulp. The produce of an ingenious physicist, JACK-5 will be more than a match for any competitor at the King of Iron Fist Tournament 5.