It's possible to get the Super Duper Combo achievement off of Nanoswarm. Just get the bananarang and fire into the place where Nanoswarm so that the bullets bounce into Nanoswarm's pit, but don't go inside of it. You can go inside to blast him into small parts to make it easier to get 15 kills in a row, but leave once he starts getting small.
 "Robot Wants Ice Cream"){kind=icon}
 "The Final Death Wish"){kind=icon}
 "UPGRADE COMPLETE!"){kind=icon}