Card-Jitsu

Card-Jitsu is a two-player game which was located in the Dojo. It was originally released on August 14, 2017.

To get there, players needed to go to the Dojo Courtyard and enter through the double doors. Belts could be earned by winning enough matches.

It was removed on September 25, 2017 for bug fixing, but it later returned on December 27, 2017.

The game returned on the HTML5 client on March 21, 2022.

Gameplay
Card-Jitsu is a card game in which players play against other penguins. Each turn, the player picks a card from a deck of 5 randomly drawn cards. Each card has its own point value and an element.
 * Fire beats Snow.
 * Snow beats Water.
 * Water beats Fire.
 * If same element, highest number wins.
 * If same element and same number, it is a tie.
 * You have to get different color of each element or three different colors of the same element to win the game.
 * Power Cards have special animations.
 * They are also supposed to have special effects e.g. a player can't use a specific element for a round. However, these do not work.

Rewards
You couldn't earn coins while playing this game, but after playing a certain number of games, players were rewarded with a belt. Belts go up in tiers going from white to black. When they reached black, they must fight Sensei to earn their mask which granted players access to the Ninja Hideout. Cards can be earned through limited use codes.

Trivia

 * There is a teaser that says "Stay ready. Look to the mountains, the elements are coming."
 * It could be played for around an hour during the Open Beta Party, but it was heavily glitched and things would freeze. The game was then shut down temporarily as things could be ironed out.
 * From July 26, 2017 until August 2, 2017, you could spot some penguins coming from behind the Pizza Parlor in the Plaza. You could also see one coming from behind the Gift Shop in the Town. These are predicted to be ninjas, meaning this was done to tease Card-Jitsu. From August 2, 2017, you can see ninjas through the windows of the Dojo.
 * Card-Jitsu was originally meant to be released on August 11, 2017. But was delayed due to server fixes. It was delayed even further on August 12, 2017, as more bugs were found that prevented the team from releasing the minigame.
 * The player will always lose against Sensei until they get their black belt.
 * There was going to be an update for the game which included a leaderboard, but it was cancelled. It is unknown if it will ever come.
 * Some time around April 2019, so many people showed up at the Dojo that starting a match would usually show the screen saying "Lost connection."
 * Beginning in March 2022, players could reset their progress if they wanted to. After doing so, all belts and the Ninja Mask will be removed from the player's inventory and they will lose access to the Ninja Hideout. In return they will receive 10,000 coins. This feature can currently only be used once a year.

Glitches

 * Sometimes you'll go up against an orange penguin with a slightly off color Orange Ninja Belt named "undefined".
 * Sometimes even, both players are orange, have an off color Orange Ninja Belt and no deck of cards.
 * Sometimes the card that you pick will remain on the screen and won't go away. It'll either appear hidden, transparent, or normal.
 * Sometimes if you click a mat with someone on it, you'll sit on top of them which causes the game not to load.
 * Sometimes the cards do not load all the way only having the number but not the picture.
 * Occasionally, picking out a card will pop up an "invalid card" error message, and disconnect you from the game.
 * Sometimes the match won't load at all, leaving it empty until you either reset your page or quit the match.