Commander Keen 1-3 Score format
Commander Keen 1-3's high scores are stored in the file SCORES.CKX The files are 204 bytes long. There are seven entries, divided up into sections stored sequentially.
0 28 Scores The scores fore each entry; each entry gets four bytes. The game usually orders these from smallest to largest, but this doesn't always have to be the case. 28 56 Items For Keen 1, whether Keen got the joystick, battery, etc; each entry is two bytes long, a value of 1 being yes. 84 14 Cities For Keen 2, how many cities Keen has saved, each entry is two bytes. Values between 0-8 98 14 Blank? Doesn't seemed to be used by Keen, 7 2-byte entries. 112 91 Names Entry names, each 13 bytes long, including terminator. The game limits names to 8 letters. 203 1 End File terminator.
This format has been reverse engineered several times, always by the Commander Keen 1-3 modding community.
The default scores are stored internally and a score file created if one is not present at startup. The default scores are 'Yorpy' 'Gargile' and 'Zzapp!'