Contra: The Alien Wars

Contra: The Alien Wars
Also known as: Contra Spirits (JP), Probotector 2 (EU) Developer: Factor 5 Publisher: Konami Platforms: Game Boy, Super Game Boy Released in JP: September 23, 1994 Released in US: October 1994 Released in EU: 1995 This game has unused code. This game has a hidden level select. This game has regional differences.

Factor 5 turns the classic SNES game into a not-so-classic Game Boy game.

To do: Document the prototype versions. Source

Level Skip

Enter H2F2 as a password, then press Start during gameplay.

Unused Invulnerability Flag

The secret passwords in this game store their flags in RAM address $C1E4. While bits 0-4 correspond to the five secret passwords, bit 5 is completely unused, and enables invulnerability. It's possible that an additional sixth secret password was planned to be included at one point.

To enable invulnerability, change RAM address $C1E4 to $20. Note that the only enemy able to damage you in this mode is the flying enemy in Level 3 that grabs you and flies off the screen.

Regional Differences

The European version continued the tradition started with the first NES game of replacing the human player characters with robots in order to circumvent German laws prohibiting the sale of violent games to minors. This would be the last Contra game (outside later Virtual Console releases) that underwent such a change.

Title Screen

Japan	US	Europe

As with previous entries, the title differs between regions. The US version drops the "III", while Europe drops the "Super" and "Alien Rebels" and adds a "2", leaving the Japanese version as the only one that's actually named just like its home console counterpart. In addition, the European version shows the two halves of the "2" sliding into place and glowing softly; the Japanese and US versions are not animated at all.

Cutscenes

Japan/US	Europe

In addition to the character design change, the Super Game Boy palette used for cutscenes was changed from yellow to blue.

Main Character Sprites

To do: This is a mess! Clean it up a little.

Japan/US	Europe

All the main character sprites are different.