A COB (also cob, COb) is a Creatures Object - an object in the game for either Creatures or Creatures 2. These objects are stored in .cob files, which contain an image (or images), a description, and some CAOS coding. In Creatures 3 and Docking Station COBs are known as agents.
Those who make COBs are known as COBblers.
Many older C1 COBs are linked to from CObfinder General, Norntropolis and TazzMann's CREATUREs UNIVERSE, and a good list of C2 COBs can be found at Creatures of Avalon. There is a growing list of C1 COBs on GirlySatan's Creatures Webpage. Unfortunately, one popular site spanning all games (Where's The COB?) was taken down in late 2001/early 2002.
If you like a COB, why not add it to the list of known COBs?
Cobblers should include a readme text file detailing specifics of how to install their COBs, but this is a rule of thumb.
Caveat: Installing too many COBs can cause clashes or overwhelm the world's scriptorium (sum total of all CAOS coding in the given world).
- .cob files go in the main Creatures directory (usually C://Program Files/Creatures)
- .rcb files go in the main Creatures directory
- .spr files go in the Creatures/Images directory
- .wav files (if present) go in the Creatures/Sounds directory
- .cob files go in the Creatures 2/Objects directory
Files with the extension .RCB are RemoveCOB files, which remove Creatures 1 COBs and their scripts. Every C1 COB should come with an RCB, but for those that don't there is the Universal Remover Spray. BoBCoB and CrEd32 can automatically generate RCB files from any COB file.
An RCB file is simply a COB file with an install script that removes agents and event scripts. They typically set every other field to a default value and don't include a picture.
For the original Creatures, there are no official cob-making programs - BoBCoB is probably the most popular unofficial one - but there are both official and unofficial tools for Creatures 2.
Creatures 1's COBs/RCBs are simpler than all later COB/agent files. As with all Creatures file formats, they are in little-endian order.
They are simply defined as such:
|2 bytes||integer||COB Version (I've only ever seen 1)|
|2 bytes||integer||Quantity Available (for injecting)|
|4 bytes||integer||Expiration month|
|4 bytes||integer||Expiration day|
|4 bytes||integer||Expiration year|
|2 bytes||integer||Number of object scripts|
|2 bytes||integer||Number of install scripts|
|2 bytes||integer||Number of install scripts used already (for injecting)|
|varies||0 or more string blocks||Object scripts|
|varies||0 or more string blocks||Install scripts|
|4 bytes||integer||Picture storage width (always matches size of data)|
|4 bytes||integer||Picture height|
|2 bytes||integer||Picture width (always matches picture storage width)|
|varies||picture data||Picture. Encoded with one 8-bit palette index per pixel (like SPR data), vertically flipped (e.g. first row is the bottom row, last row is the top row).|
|varies||string block||COB Name|
|varies||string block||COB Description|
String blocks are defined as follows
|1 byte||integer||String Length (if 255, use second string length)|
|2 bytes||integer||String Length (if first string length was less than 255, this string length does not exist)|
|varies||string||String (If this is a script, lines of CAOS are comma-separated with no whitespace between them)|
Creatures 2's are block-based, like the successive PRAY format. As with all Creatures file formats, they are in little-endian order.
The format is simply:
|4 bytes||'c' 'o' 'b' '2'||File magic identifier|
Where a chunk is:
|4 bytes||data||chunk type|
|4 bytes||integer||size of chunk data|
There are three known chunk types: agnt, file, and auth.
|2 bytes||integer||Quantity remaining|
|4 bytes||integer||Time of last use (in seconds since midnight UTC Jan 1, 1970)|
|4 bytes||integer||Reuse interval in seconds|
|1 byte||integer||Expiration day|
|1 byte||integer||Expiration month|
|2 bytes||integer||Expiration year|
|4 bytes||integer||Unused, should be zero|
|4 bytes||integer||Unused, should be zero (originally intended to be flags)|
|2 bytes||integer||Unused, should be zero (originally intended to be x-position)|
|2 bytes||integer||Unused, should be zero (originally intended to be y-position)|
|varies||null-terminated string||Agent name|
|varies||null-terminated string||Agent description|
|varies||null-terminated string||Install script|
|varies||null-terminated string||Remove script|
|2 bytes||integer||Number of event scripts|
|varies||0 or more null-terminated strings||Event scripts|
|2 bytes||integer||Number of dependencies|
|2 bytes||integer||Dependency type|
|varies||Null-terminated string||Dependency name|
|2 bytes||integer||Thumbnail width|
|2 bytes||integer||Thumbnail height|
|varies||565 picture data||Thumbnail|
|2 bytes||integer||File type - 0=.s16, 1=.wav|
|4 bytes||integer||Unused, should be zero|
|4 bytes||integer||Size of file|
|varies||null-terminated string||Name of file|
|varies||data||The file data itself|
|1 byte||integer||Day file was created|
|1 byte||integer||Month file was created|
|2 bytes||integer||Year file was created|
|varies||null-terminated string||Author name|
|varies||null-terminated string||Author e-mail|
|varies||null-terminated string||Author URL|
|varies||null-terminated string||Author comments|