Under the microscope: Urban Chaos (Dreamcast)

Everything is open source when you can read machine code, but sometimes the original source is available.

In this edition, I’m examining Urban Chaos. This was game one of three developed by the UK studio Mucky Foot Productions. It was released for Windows PCs in Europe in 1999, and console versions appeared for PlayStation and Dreamcast the next year.

This article is about the Dreamcast edition. Its manual has an ad for Eidos’s Interactive Hint Line, which it exhorts you to call if you get stuck:

From page 1 of the U.S. version’s manual

I’m hear to save you $0.99 per minute – there are heretofore-unnoticed cheat codes for this game! Below are details on how they work.

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The codes

If you search for the string cheat in this game’s memory, you’ll find:

000faa34  "Y R R A B Y R R A B"
000faa48  "OK, fast cheats enabled, D’arci."

It raises certain questions: Is this a button sequence? Where do you put it in? What are fast cheats? Amazingly, the answers are available in the game’s source code – one of main developers posted it to GitHub several years ago. It says:

if ( BUTTON_IS_PRESSED ( the_state.rgbButtons[DI_DC_BUTTON_LTRIGGER] ) && BUTTON_IS_PRESSED ( the_state.rgbButtons[DI_DC_BUTTON_RTRIGGER] ) )

Oh, so hold down R and L. A bit later it says:

// Now look for strings. Remember, these are _backwards_.
if ( IS_STRING ( "Y R R A B Y R R A B" ) )
{
    // BARRY BARRY
    // Enable the fast-key cheats.
    CONSOLE_text("OK, fast cheats enabled, D’arci.");
    g_bCheatsEnabled = TRUE;
}

Later, the source explains what the fast cheats are. First hold L+R and enter B, A, Right, Right, Y, B, A, Right, Right, Y, then:

• Hold L+R+Start and press Up to restore health

• Hold L+R+Start and press Down to spawn guns

• Hold L+R+Start and press Left to spawn ammunition

• Hold L+R+Start and press Right to show D’arci’s position

These do indeed work in the released build:

The source refers to more cheat codes also. Hold L+R and enter A, B, X, Y to see this goofy message:

There’s also this one: Hold L+R and enter Y, A, B, B, A, Down, A, B, B, A to complete the current stage.

And this one: Hold L+R and enter B, A, B, Y, Down, Up, Left, Left to control the draw distance. After putting in the code, hold L+R again and use the analog stick to make changes.

The source also refers to LARALARA for unlocking all levels and BLADDUR for toggling “inflation” (?), but these don’t work in the final release.

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Outro

The PlayStation version of Urban Chaos doesn’t seem to have these in-game cheats. But it does have an “all levels” cheat that can be enabled from the main menu. This has been on GameFAQs et. al. for ages, but it’s shown in the source snapshot, too.

More explorations in retro game reverse engineering are coming soon! Leave a comment with suggestions about games to check out.

Logo by Ashlyn Anstee