Expansion hack: Elemental Gimmick Gear (Dreamcast)

I am the Eggman

Birthday, a Japanese development studio, produced exactly one game for Dreamcast. And Vatical Entertainment, an American publisher, published exactly one game for Dreamcast. That game was E.G.G. — Elemental Gimmick Gear.

E.G.G. is an action RPG. It got decidedly mixed reviews — EGM’s reviewers called it “decent” but “bland,” and criticized the English translation. Official Dreamcast Magazine said it was charming, but couldn’t escape “the curse of being average.” Whatever — I liked it.

In this edition I’ll be upgrading E.G.G. with a one byte patch that enables debug controls. Download the patch from SegaXtreme and see the details below!

You can name the character whatever you want

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The patch

This string stood out to me in the memory snapshot for this game:

8c4f44e8 "Debug Main MENU"

Tracing references to that leads to the function at 8c49d35e. It checks whether there are bits are set in the value at address at 8c194778, which is normally C0 — debug functionality is totally suppressed.

Changing that value to 00 fully activates debug mode, but it’s too much data! You can barely see the characters:

A value of 40 is much better. This exposes debug controls, but keeps most of the information display suppressed.

My patch bypasses the flag check entirely, allowing the controls the be activated without the debug counters:

8c49d386 0900  # Don't skip past the debug controls

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Debug controls

The debug menu controls aren’t easy to intuit, but I eventually managed to puzzle them out. Hold R+Down to toggle hit boxes and display debug info:

After you’ve done that, hold B+Right to bring up the main debug menu:

This menu behaves a bit more intuitively. You can adjust player stats and parameters, which is useful:

There’s also a nice sound test:

But the star of the show is the map switcher. Hold L+Up to display it:

You can warp anywhere in the game by adjusting the location components. Cool!

These controls don’t work in the 3D sections of the game, alas.

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Outro

For more game mods from me, check out my Expansion hacks archive.

I’m always looking for new games to examine for hidden secrets like this. If you’ve got ideas for which ones might be promising, tell me about them in the comments.

Logo by Ashlyn Anstee