When you find the transceiver in the prototype version of the game, enter any door thereafter. Then select "Tools", highlight "Transeiver", and hold Down, A, and B on Controller 2, then press A on Controller 1. A secret message will appear each time you press A.
No Health from Konami Man
Find a secret door with Konami Man and punch him or hit him with the hammer. Now everytime you find him in the game, he says he cant heal you because you hit him.
Passwords
Effect
Password
All items and Goonies
K'O N248 4SR ''OOS
All Items and No Goonies
H4O N4(left arrow)(right arrow) '7R 3 ' ' E
All Items Unlocked (PAL Version)
SugNY4wT!NUU!!uF
PRG CRC Test
At the title screen, hold A+B, and hit start. You'll access a short PRG CRC test.
Startup Glitch (Japanese Version)
Turn on the game, hold Select and press Reset. Let go of Select and wait for the demo to start. Once in the demo, wait for Mikey to die and when Momma Fratelli starts to talk, press Start. If done right, you'll start on the same level as the one in the demo. If you want to start on a different level, just wait until the demo starts, press Start or Select to go back to the title screen (before Mikey dies) and wait for the next demo to begin. Repeat the process above to start on that level.