Variable string to add to a patterned end, likely needs script but not good at programming

Okay so I currently have about 11,000 images all patterned up. There are 1100 folders roughly, and in each of those folders are 5 images, each following a pattern.

So each folder has 4 images with the words "avatar" along with a direction (like ne for northeast for instance to create "avatarne"). Then the 5th image has the word that I want the other 4 images to have at the start with proper casing, these are pictures of animals so in one case it'll be "deer" or "eagle" or something else, but I want that string as a pattern in the front of the other 4 images. So an end desired result would be "deeravatarne" without quotes.

Is there a way for me to stitch the string that I want from this singular image onto the other 4 while doing this in batch since there are a million folders all following this select pattern? Or is that too complicated for this program?