Le premier dragon

The two-star dragon, Haze Shenron, is severely polluting the entire area, so Pan steps in to stop him. She is much more powerful than the dragon and relentlessly beats it up. But Pan's attacks seem to do less and less, until the dragon is able to overpower her. Goku tries to transform into a Super Saiyan and finds that he is unable to. The dragon explains that his pollution causes all living things to exponentially weaken, die and decay over a short period of time. This is why Pan's strength is gone, and why Goku can't power up. He also reveals that he was created when Goku wished to revive Bora, father of his old friend Upa, after he was killed by Mercenary Tao, horrifying Goku with the fact that he was indeed responsible for the creation of the Shadow Dragons. The dragon beats them up, and then throws them into the lake. Giru, who is unaffected by the poison due to being a robot, goes underwater and pulls them to an uninfected part of the lake. There is a spring here that is feeding in pure water from underground, keeping the area clean. Goku blasts the hole, flooding the lake with clean water. With their powers rejuvenated, Goku and Pan destroy the dragon quickly before his pollution has enough time to take effect and recover the two-star ball, which returns to its original form. (Source: Wikipedia)