Use this to download this category as MP3 with youtube-dl:
declare -a list=("https://www.youtube.com/user/MissingnoXpert" "https://www.youtube.com/user/MrCheezeMrCheeze/videos" "https://www.youtube.com/user/v0id19/videos" "https://www.youtube.com/user/TheZZAZZGlitch/videos" "https://www.youtube.com/channel/UCwRqWnW5ZkVaP_lZF7caZ-g/videos" "https://www.youtube.com/user/jrosereveiws/videos" "https://www.youtube.com/user/JohnP176/videos" "https://glitchcity.info/wiki/Main_Page" "https://bulbapedia.bulbagarden.net/wiki/Save_data_structure_in_Generation_I" "https://www.youtube.com/channel/UCWfyrsa3sxAjtZZ1WFBkoBA/videos" "https://www.youtube.com/channel/UCfI2t193cJoo4WQsZCP3RXw/videos")
for val in ${list[@]}; do
name=$(basename "$val")
if [ -e $name ]
then
continue
fi
mkdir $name
cd $name
youtube-dl -f mp3-128 $val
cd ..
done