Secret Flea Area:
In the Lower East Quack level, go past the section where you hitch a ride on the subway and proceed along until you see
a brown fence with a hole in the lower left side. Turn
left to find a Change transport. Once you are Change, go through the hole, and
go on to the boxes beyond. When you get there, Change will star scratching
and you will be transported onto his back as a flea with a heavy-duty machine-gun.
