Experiment 616 was the 616th genetic experiment created by Jumba with Hämsterviel's funding. He was designed to create huge craters.
616 and the other first 624 experiments were deactivated and smuggled to Earth by Jumba during his mission to capture Experiment 626.
All of the experiment pods were released and scattered across the island of Kauai.
Joey is a red kangaroo-like experiment with 2 spikes running down his back, 2 rabbit-like ears, big yellow eyes, and has scarlet markings on his back.
Joey can jump into the weakest part of an atmosphere, the border of the atmosphere and space, then come crashing down so hard he knocks the planet out of orbit, and hope it will fly into another or into a star. As soon as he touches the ground, he jumps up at light speed, going a 1 lph (lightyear per hour) and land on another planet, knock it out of orbit, and so on.
After a while, everyone will start to notice the missing planets, and try to protect theirs. Joey was programmed in hope that this would happen. The military for that planet will sit in one area, waiting for Joey. When they see him coming, they will try to shoot him. With his amazing speed he will miss, but he was made indestructible just in case. He then turns himself magnetic, and attracts the bullets, then once they attach, he absorbs the bullets through his skin. Then he spits them out in all directions through his mouth, after he adds explosive fluid to them. They will then explode on the military, but most of the bullets would actually land miles from there, destroying some cities. After he spits out the bullets, if he's content with the destruction, he'll suddenly change direction and should barely miss the planet. He then continues his path of destruction.