Update by Nick Bullar
You can type these codes during the game:
HATMAN - Stick figure (Jim changes into hatman)
IDDQD + IDKFA - Various credits
THREEMILEISLAND - Full life
ITSAWONDERFUL - Extra life
ONANDONANDON - Full continues
POPQUIZHOTSHOT - Full ammo
JUSTWHATYOUSEEPAL - Full plasma
ROMARIO - 1st 7 levels
GETTHECHEESETOSICKBAY - All levels
BLOATED - Afro
FESTERING - Red afro
PULSATING - Novalty glasses
PUSFILLED - Antenna
SLAUGHTERHOUSE - Access to first 5 levels on the file menu
SWEATY - Makes Jim have big lips
MALFORMED - Makes Jim have glasses
SLUGFORABUTT - Makes Jim have an arrow thorugh his
head and a weird face
APOLLO 13 - Gives you 9 rockets!
You will hear Jim call you a 'Cheater' when you type in the code
* Successfully complete the game under the easy difficulty setting to view
a long text about worms. Successfully complete the game under the normal
or difficult setting to display an animation in which Jim meets Princess.
After the credits complete, another animation will play.
* In the ending sequence under the difficult difficulty setting, Jim will go
on about how you are the best and that the company cares about you.
* Note: Play track 23 of the game disc in an audio CD player to hear hear the
speech about worms for the easy difficulty setting ending. Notice that Jim
knocks you for playing on "practice" mode, however this is a mistake as it
is "easy" mode, not "practice" mode. Play track 27 to Earthworm Jim praising
you from the ending for the difficult difficulty setting.
Sometimes while walking, you will hear a sheep and see some swirling lights.
This means that part of the level has changed. Backtrack to find extra health
power-ups or ammunition.