Also known as: Ikari no Yousai (JP)
This game has regional differences.
The 'Password' option was changed to 'I.D. Code' for the US/EU release.
The password screen in the Japanese version includes all letters of the alphabet. The US/EU switches them out for the feeble numbers 1-8.
The typo in the Japanese version menu fixed in the US version.
"Walk through walls" Glitch
Even though the Japanese version was released before the US and European versions, there is a glitch in the latter versions that allows you to walk through 8 pixel wide walls. This glitch does not work in the Japanese version.
YURI KEI! AMI! RIE! MOMO EMI! MAI! YUU! MINT ELI! REI! SAKI YOKO RISA KAYO RUMI MAMI JUN! TAE! NAMI MIA! GAMI RIKA ERI!
A set of special passwords that were only usable in the Japanese version, stored at 13C90.
In the US version, these passwords are all that remain of what the Japanese version used, which included three more sets: The game's normal passwords, and the ones that give infinite energy for each of the two characters. Any of these above passwords, if used in the Japanese version, will give Mizuki 'SD' style graphics and change the regular shots into hearts. Attempting to use these passwords in the US version by manipulating the values via patch codes will simply return invalid.
Whereas each column starts the player on a different stage, the first row is for normal play, but the others will give infinite energy and weapon power, as well as affect who the starting character is and start Masato off with the flame thrower.