every time i play co-op, i try the following: escape upstairs, camp phd until power. back to phd where we both purchase only phd. we do this early as we can. survive through two monkey rounds without jug. all you gotta do is protect phd as that is the only one the monkey can go after. by the end of monkey round 2, hope you both got jug, if not, mad-dash to juggernog machine.