When Max was called by Ven-Ghan to find Evil Ultralinks, Max goes to an alley ending in a dead end, but is unaware of the fact that bullies from school were following him. There, they were going to hurt him until Bartholomew 'Butch', their old leader, told them not to, and Sydney and Kirby "scared" them off. Then, the Ultralinks that had really scared the bullies, bonded with Sydney and Kirby, one creating the Soda Link.
When Butch, Kirby and Syd followed Max, they were accidentally connected with Evil Ultralinks, and Kirby became a "Soda Link" because he had a cup of soda in his hands.
Since they had no control over themselves, they began to attack Max, and Kirby attacked with a wave of soda. Although that Max and Steel fought back, they lose the battle, the Ultralinks then fled and Ven-Ghan appeared. Max says then that he desperately needs to find his friends who were linked with Ultralinks.
Steel then finds out that they are in the sewers, and there, Ven-Ghan uses his Ultralink to find them. When they find Kirby and the others, the Ultralinks attack and Max and Ven-Ghan are thrown in an empty water reservoir. There, of the group, Kirby was the first to be unlinked, because Max made Kirby remember how he loved food, aluminum pants, and that he was in a band. Immediately, Kirby remembered who he was, and was succesfully unlinked by Ven-Ghan.
Superhuman Strength: Since Kirby was linked with an Ultralink, he was enhanced and got weapons on his hands, them being a blade and a cannon.
Soda Cannon: Kirby Link has a cannon on his left arm that is able to shoot a wave of orange soda.
Kirby just got this transformation because he had a cup of soda on his hand. If he didn't had one on his hands, he would have gotten another transformation.