I'm left wondering what the other weapons actually did. I upgraded cannonball and the actual ship upgrades before the other weapons, and then I beat the game. It could have been harder though. I never died until I touched the wall of the boss room
OMG The Pascals Law lvl took me FOREVER...
Played it for a solid 15 minutes...almost about to quit...then I read the TITLE... /FACEPALM
I guess the titles are quite descriptive
 "Pirateers"){kind=icon}
 "One Step Back"){kind=icon}
 "Spewer"){kind=icon}