you can have as many as you want just buy them they are worth it
There was 39 but with the new fire packs it is now 45 not 51.
There are 10 cards in a Club Penguin Card-Jitsu starter deck.
You need to buy them at Toys R Us and then type the code on the card on the website to earn the prize which is using that in Card Jitsu
It is the Rockhopper card. It's unbeatable because it is 12 water and if someone plays a snowball card it turns the snowball card to water so the worst it can do is tie/draw.