Oooh, that means you've got about twelve kilobytes to fit your Doom into. Or your bootstrap routine that connects to some other device connected to the Gameboy

Oooh, that means you've got about twelve kilobytes to fit your Doom into. Or your bootstrap routine that connects to some other device connected to the Gameboy Advance and downloads your actual Doom. Whether or not this counts as "running Doom on this device" is open to argument.