Free Art Source - Pixabay.com!

Pixabay.com is a website with the purpose of providing art, photographs, and videos for free.

The images can be searched for by whether they are photographs, vector graphics, illustrations (including CGI), or videos.  Furthermore, you can search by if the image is in portrait or landscape orientation, and by several broad categories, like Nature/Landscapes.  

When you find a picture, you can download a smaller resolution version for free, under a Creative Commons 0 license.  A larger version is available if you sign up for free.  Pixabay is partnered with Shutterstock, so make sure you are careful not to fall in love with the first image you see - there is a line of Shutterstock content for sale up the top of all search results, and to the right.  

There are some oddities with spriting for the Creatures series that Pixabay images  may need to be altered to fit - in particular, pure black  appears transparent in-game.  However, Pixabay has a wide variety of free art which could easily be adapted into background images for digital collage metarooms.

Free Art Source - OpenGameArt.org!

OpenGameArt.org is a website with the purpose of providing "a solid (and hopefully ever-expanding) variety of high quality, freely licensed art, so that free/open source game developers can use it in their games."

It has several different kinds of art available on the site - 2D art (including pixel-style art), 3D art, concept art, textures, music, sound effects, and documents such as tutorials.

The search bar allows you to search by the license that the artwork has been released under - if you need something that's compatible with what you want to do with the artwork.  CC0, or the public domain, is generally the freest possible license, but it's worthwhile finding out about the terms and conditions of the other licenses to find out if they can suit your purpose.  Licenses which are just "CC-BY" and a version number are usually pretty easy to comply with, as well - you have to say who created the artwork and link back to them.  A list of all the licenses available on the site, and what they mean, is available under their FAQ.

There are some tagging features, but I haven't been able to find a tag cloud yet - you might like to browse through the animated, sidescroller or platformer tag for potential critter sprites.

There are some oddities with spriting for the Creatures series that these sprites may need to be altered to fit - in particular, pure black  appears transparent in-game.  However, OpenGameArt has a wide variety of free art which could easily be adapted into Creatures COBs and agents.

How to Convert a C1 SPR File to a C3/DS C16 File

How to convert a C1 SPR file to a C3/DS C16 file, using The One Stop Sprite Workshop and Jagent.

Get The One Stop Sprite Workshop and Jagent.

Choose a SPR file to work with. If it is an official Creatures 1 sprite, then Gameware’s general copyright exception applies, but with other sprites, it’s a good idea to get the permission of the original COBbler.

Open the SPR file with The One Stop Sprite Workshop. If you navigate to the folder that your sprite is in, but you can’t see it, make sure that you check that the ‘Files of type:’ dropdown is showing ‘Creatures 1 Sprite Files (*.spr)’.

You should see a small preview with a black background. Go to File > Save As and choose ‘Creatures 2 Sprite Files 16 bit format (*.s16)’, and save it with a sensible name. Close The One Stop Sprite Workshop.

Open this S16 file with Edos, and you should see the agent itself with a blackish border, without a background. Go to Save and save it with a sensible name, AND the .c16 extension. (For example, saving a lemon sprite as lemon.c16). In addition, you have to use Edos’s dropdown option to choose ‘Files of Type’ ‘Compressed Sprite File (*.c16)’.