The prettiest way to do this would be to use alpha-masked PNGs (instead of the usual PICT graphics, which just use "white = fully transparent, all else = opaque") so that you can use partial transparency in your creature.
(If you're not familiar with graphics formats and the nature of alpha masks, may I (less than modestly :)) suggest looking at (url="http://"http://www.ambrosiasw.com/webboard/Forum48/HTML/000518.html")http://www.ambrosias...TML/000518.html(/url) )
This method might slow your game down appreciably, especially on slower systems, as I believe that Coldstone's translucency engine is not particularly optimized (notice how slow Pillars of Garendall gets when you walk around campfires or spiderweb-filled crypts - two places where it uses translucency fairly heavily).
An alternate method which would be less pretty but probably somewhat easier on the game engine would be to fake translucency by dithering the images with white. That is, make every other pixel in your image white so that that background objects will show through in places. This is a lot less pretty, but it may be worth it for the speed boost.
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I would rather discover a single fact, even a small one, than debate the great issues at length without discovering anything at all. - Galileo Galilei