The Jack robot series
was partly created by Dr. B. The original
Jack is from Tekken 1, Jack-2 is from Tekken 2, Jack-3 is Gun
Jack, Jack 4 was never playable in a game but can be seen in the Tekken
5 intro, Jack 5 is the playable version of Jack in Tekken 5, and Jack-6
of course is in Tekken 6.
Jane created Jack-5
him as an upgrade of Jack-4 and used the fifth tournament as a means of
testing Jack-5. Returning to have his emotion program installed, Jane downloads
Gun Jack's memories into him, but the results cause him to go berserk,
ripping free and trashing the lab. As he brings down his arms in a crushing
blow on Jane, the memories re-assert themselves and Jack stops, looking
over his body in confusion. Jane goes to him and he picks her up in his
arms gently, his original personality fully restored.
After Jack-5 had returned
from collecting combat data at the King of Iron Fist Tournament 5, it returned
to G Corporation's laboratory where Jane proceeded to run advanced combat
algorithms based on its research. Soon afterwards, war between the Mishima
Financial Group and G Corporation broke out. And just as large numbers
of production model Jacks were being dispatched to all parts of the world,
unconfirmed reports stated that the Mishima Financial Group had drawn up
plans of their own to imitate the killer robots. The audacity of someone
coping her Jack angered Jane greatly; thus, she sent Jack-6, the newest
Jack, to investigate the incoming reports.