Ok, got it: there is a mistake in the rules! It should be 24, you are right!
Thanks for the catch!
Hey thanks for the comment! In the end I think there are much better offerings in the competition, but I take a compliment any day :-)
To come to your question:
You have two use two full decks of cards (minus the Jokers).
Hence:
3 figures per suite, 4 suites per deck = 12 cards per deck
Times two decks = 24 cards make up the entire Target deck.
Does it make sense? Or where is the mistake?
Cheers!