Tusk

Tusk is an evil walrus. He used to be the best friend of Sensei, but turned on him due to jealousy.

History
Tusk was born in the 1870's. His parents are unknown, for he washed up on Club Penguin Island in a crate box all alone. He was adopted by two native ninjas that had compassion on him and vowed to train him as a ninja as well.

When Sensei was young and had not yet learned Card-Jitsu, he used to play with Tusk. They played together, had snow ball fights and seemed to be good friends. Soon, Sensei and Tusk both began to train in the art of Card-Jitsu. Like best friends, they both 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 snow moves of Sensei. One day, they chose to have a battle on a snowy cliff, where the future Snow Dojo would stand years later. Tusk initiated it by throwing a snowball at an u-prepared 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. He vowed to teach Card-Jitsu, especially Card Jitsu Snow, to penguins so they could use the power of the elements wisely. Tusk presumed Sensei had left not caring for him, and turned bitter.

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 three Snow Minions, Scrap, Tank, 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 challenge, the ninjas had to stand up to Tusk in a battle that would determine the fate of the island. Tusk is said to have laughed maniacally, saying that their Sensei had taught them well, but he has more power than all of them. Turning into a shadowy spirit, Tusk disappeared.

Trivia

 * He's not counted as the first walrus who came to Antarctica, because he floated there in a box, and didn't come there, as said above. Instead, Walrus is counted as the first walrus who came to Antarctica.
 * Nobody knows how he has such longevity, living to over 140 years. Many think he had learned how to keep himself alive through his lust for power.