A new Card Jitsu code has been released as part of the (currently) ongoing Club Penguin Rewritten Devcast! These can be used whilst playing Card Jitsu or Card Jitsu Fire. The code is CARDJITSU3003.
It can be redeemed by clicking “Unlock Items Online” in the top right corner of the servers page and then “I’ve got a code”, then enter in the codes.
If you’re looking for some physical Card Jitsu cards, check out this post. 😉
Be sure to redeem the code before it expires!