Easy way to get the hard badge is to get the unlimited jump boost, with max regen and armor upgrades if possible. Then just keep jumping off the top of the screen so most enemies can't hit you. Drop down for health upgrades whenever you see them as the 3rd boss will regularly hit you for more than the regen can heal you.
 "Cyber Chaser"){kind=icon}
 "Jelly Blocks"){kind=icon}