Unwrapped code block prevents further edits

After adding all the cards, open the command line (Terminal.app). Copy and paste the code below.

mkdir ~/Desktop/cards
files=(~/Library/Passes/Cards/*.pkpass/cardBackgroundCombined@2x.png)
i=0
for f in "${files[@]}"; do
    i=$(( i + 1 ))
    cp $f ~/Desktop/cards/$i.png
done