COB

COBs are added to the world using the Injector (Updated C1 edition pictured).

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.

Finding COBs

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?

Installing 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).

C1

• .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

C2

• .cob files go in the Creatures 2/Objects directory

RCB Files

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.

Developer information

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

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:

Length	Type	Description
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
4 bytes	integer	Quantity Used (for injecting)
varies	0 or more string blocks	Object scripts
varies	0 or more string blocks	Install scripts
4 bytes	integer	Picture width
4 bytes	integer	Picture height
2 bytes	integer	unknown (always seems to be the same as the picture's 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
1 byte	integer	COB terminating 0x00 byte

String blocks are defined as follows

Length	Type	Description
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

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:

Length	Type	Description
4 bytes	'c' 'o' 'b' '2'	File magic identifier
varies	chunks

Where a chunk is:

Length	Type	Description
4 bytes	data	chunk type
4 bytes	integer	size of chunk data
varies	data	chunk data

There are three known chunk types: agnt, file, and auth.

Agnt chunks:

Length	Type	Description
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	Must be zero
4 bytes	integer	Must be zero
4 bytes	integer	Must be zero
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

File chunks:

Length	Type	Description
2 bytes	integer	File type - 0=.s16, 1=.wav
4 bytes	integer	Must be zero
4 bytes	integer	Size of file
varies	null-terminated string	Name of file
varies	data	The file data itself

Auth chunks:

Length	Type	Description
1 byte	integer	Day file was created
1 byte	integer	Month file was created
2 bytes	integer	Year file was created
1 byte	integer	Version
1 byte	integer	Revision
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

Related links

• Agents
• Modding in the Creatures series

External links

• BoBWare (C1/C2) (archived)
• Creature Labs' Technical COB Information for Creatures 2