Tusk

Tusk is a walrus and the lead antagonist at the Card-Jitsu Party 2013. He is the one who sent Scrap, Sly, and Tank out to defeat Sensei and destroy the Dojo. Tusk seems to have hatred for Sensei and his Ninjas, and is from Sensei's childhood, being Sensei's best friend, but turning on him out of jealousy. You can battle him after receiving the Snow Gem.

History
When Sensei was a young boy who had not yet learned Card-Jitsu, he used to play with Tusk. They swang and had snow ball fights and seemed to be good friends. One day, when Tusk made some snowballs, Sensei made a snow statue of the future dojo. Tusk seemed bitter at this, sensing Sensei would later become more involved in it. He became jealous and angry. Sensei and Tusk trained to master the elements together. They dreamed of standing side by side, leading and training an army of ninja penguins. He and Sensei were friends, but their relationship had a competitive side. Tusk could not master the delicate moves of Sensei. One day, they chose to have a battle on a snowy cliff, where the future Snow Dojo would be years later. Tusk instigated it by throwing a snowball at Sensei, who threw Tusk against a wall with snow. Tusk used his power to create an enormous snowball, displaying his true power over snow. He threw it at Sensei, but once it hit him Sensei sent it back. The force against the wall caused an avalanche, in which Tusk was buried and trapped in a cave in the side of a mountain. Sensei looked for him, but found only a piece of his tusk, departing sadly, and vowed to teach Card-Jitsu to penguins so they could use the elements wisely. Tusk presumed Sensei had left not caring for him, and turned bitter. He sadly sat buried in the snow, then began to dig himself out.

For years, Tusk plotted, making the cave his lair. He made armor and a torn cape for himself to look intimidating, became the leader of the snowman army, obsessed with avenging his defeat. He vowed that he would master snow, and that he would get revenge. In May 2013, Tusk sent the 3 Snow Minions, Tank, Scrap and Sly to attack and take revenge on Sensei, but Sensei and the Ninjas withstood the attack, in the game Card-Jitsu Snow. As a final challenges, the ninjas had to stand up to Tusk in a battle that would determine the fate of the island. Tusk laughs evilly, saying that their Sensei had taught them well, but he has more power than all of them. Turning into a shadowy spirit, he disappears.

Trivia

 * In the 1st scene in Card-Jitsu Snow, he was Sensei's friend long ago, but the friendship disbanded because of jealousy.
 * He is the first walrus character in Club Penguin.
 * His missing tusk is Sensei's Simple Walking Stick, turned brown by age. This most likely means that Sensei still cherished their relationship even after Tusk turned evil.
 * Judging by his departure at the end of Card-Jitsu Snow, his story may be continued if Card-Jitsu Shadow is real, he and Sensei will possibly make amends and become friends again.
 * After defeating him in Card-Jitsu Snow, you can get his cape.
 * He, Herbert, and bats are the only mammals in Club Penguin.