Creating high quality background images for a game which have small areas of moving detail
The &quot;modern equivalent&quot; of animated GIFs is... MPEG. Or really, any decent movie compression format. These techniques are designed to spend fewer bits on static areas and more bits on moving ones. And better still, they're designed to be dynamic, allowing motion in any are at any time, rather than only in fixed areas.
So just make a short, looping movie of the &quot;background image&quot; you're trying to build. You may want to get into the details of the compression system you're working with, so that you can give lots of bits to the initial frame and fewer bits to moving areas.