Board Thread:Battle Nations Discussion/@comment-33992849-20171217121923/@comment-24783341-20180205195431

Several users still seem to visit the wiki and have general interest in pursuing discussion. FANDOM (company that regulates all wikis under the wikia.com domain) is thus unlikely to close this wiki in the future.

To answer your question, I don't think there's a way to download the images and videos from the wiki in any timely manner. You'd have to find the images you want and download them to your computer individually.