As you lie down on the floor unable to move, the now muscular Jack, has revenge in his eyes.
He gets some of the weightgain formula you got for him earlier and, he just stuffs it into your enlarged blubous face.
then you get that warm feeling again... but this time it is much faster and much hotter. you get knocked out.
acouple of hours later, you wake up only to find that you still can't move, but you have out grown the building ~! and blew the roof off.