Unlock Hyper Arcade Mode

To unlock Hyper Arcade mode, beat Arcade mode with the shotgun



Unlock Might Joe Jupiter Trilogy

Beat all the Mighty levels in Cadet Training to unlock Mighty Joe Jupiter Trilogy (in MJJ mode).



Unlock Music Juke Box

Finish all episodes of the Mighty Joe Jupiter Trilogy to unlock Music Juke Box, which can be found in the options screen.



Unlock New Guns

To unlock new guns, beat the game in Arcade Mode to unlock the new weapon. Here's how:

Beat with pistol: machine gun

Beat with machine gun: cane gun

Beat with cane gun: shotgun