Hamtaro in Pieces: a disassembly of Hamtaro: Ham-Hams Unite!

This is an incomplete disassembly of the stellar, delightful, and pulchritudinous Game Boy Color game Hamtaro: Ham-Hams Unite!. Why would I disassemble Ham-Hams Unite, you ask? Because I thought I'd get some reverse-engineering and disassembly practice in, and I love this game to bits.

ROM built

This disassembly builds the North American version of the game, with the MD5 hash 48ce279084e1fc7a9136cc211f4fad5d.

I'm not from North America, but I do like variable-width fonts (which makes the Japanese version less alluring), and disassembling a language switching system would be a whole lot of pain for very little of interest (which makes for a no on the European version).

How to build

First of all, since the disassembly isn't complete, you'll have to supply a base ROM. To do this, obtain a ROM of the North American version of Hamtaro: Ham-Hams Unite!, name it base.gbc, and place it in the top-level directory. To check that you have the right ROM, you can run md5sum base.gbc and check that it matches:

$ md5sum base.gbc
48ce279084e1fc7a9136cc211f4fad5d  base.gbc

The following are required to build the disassembly:

• Crystal – for speed and fun (but mostly speed), the disassembly uses tools written in Crystal. Follow the official installation instructions!

  At the time of writing, Crystal isn't available natively for Windows, so you'll need to use WSL (available on Windows 10) and follow the Linux instructions.

• RGBDS version 0.3.6 or newer – follow the instructions in the readme on the GitHub page to install.

Once preparation is done, use Make to first build the tools, and then build the ROM itself:

make -C tools
make

Presto! The finished ROM is now available as Hamtaro - Ham-Hams Unite! (U).gbc, alongside a .sym file that lets you see all the labels in the debugger of your emulator of choice.

That's it!

Questions? Wishes? Problems? Just wanna talk? Open an issue here on GitHub or write to @obskyr on Twitter!