Nihilore

httrack \
--depth=3 \
--verbose \
--robots=0 \
+*.png +*.gif +*.jpg +*.jpeg +*.css +*.mp3 +*.js -ad.doubleclick.net/* -mime:application/foobar \
https://www.nihilore.com/

Copy only unique files:

find . -type f -name *.mp3 -print0 \
| xargs -0 md5sum \
| sort -k1,1 \
| awk '!seen[$1]++ { $1=""; sub(/^  */, ""); print }' \
| xargs -d '\n' -r cp -t /home/user/Nihilore --