Are the bosses supposed to get insanely harder once you beat them? I wiped the floor with the first boss (without upgrading once) went to fight him after getting a bunch of upgrades and barely got him to half health.
What I have learned for my next undercover nuclear destroying mission...alarms be damned...sometimes a best stealth defense is a blow 'em to hell offense.
 "Robert The Elf"){kind=icon}
 "Forbidden Arms"){kind=icon}
 "Zee and the Alien Machine"){kind=icon}
 "Stealth Hunter 2"){kind=icon}
yes they do get tougher each time. planning to put a high score on how many boss kills you did sometime in the future.