Dragon Ball Z: The World's Strongest

While looking at the Dragon Radar, Oolong notices that all of the Dragon Balls are starting to be gathered together. He and Gohan, who were also searching for the Dragon Balls, head out to investigate and end up at the Tsurumai-Tsuburi Mountains’ eternal wall of ice, where coincidentally, Piccolo is also training. Dr. Kochin summons Shenron and wishes for Dr. Wheelo’s lab to be released from the ice. The ice begins to break away and a building emerges. Gohan and Oolong look on in disbelief, when they are suddenly attacked by Dr. Kochin’s Biomen. Piccolo shows up to save Gohan, but is overcome by three mysterious fighters, while Gohan and Oolong escape.