The following cheats allow you to: be invincible; get the slave bird; morph through the different characters and get all the ammo.
1 - jjgod
2 - jjbird
3 - jjmorph
4 - jjammo
There are a few secret signs scattered around JJ2, one of them referring to a certain fish...
I can't remember the exact places of the signs, so I'll put in some of the stuff on some of the signs and you can find more (My JJ2 game somehow broke,...
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