The Ozone Hole Monster, appearing in the episode A Sunsational Surprise / A Sunsational Puzzle, lived in an ozone hole that was created from air conditioners sold by Nightmare Enterprises. These were no ordinary air conditioners - they made it so hot out during the day that no one could go underneath the sun without getting sunburned.
Kirby and his friends decided to investigate what was making it this hot out during the day, so they built a hot air balloon and went up there, where they found the hole in the ozone layer and dropped a bomb on Cappy Town, which was actually a warning in disguise that Dream Land was in danger of being seared by ultraviolet rays.
The kids decided to have Kirby stop the hole from growing even more, so they summoned the Warp Star, and as Kirby rode it over to the ozone hole, the monster revealed itself. Its attacks mainly revolve around breathing UV rays from its mouth like lasers. The UV rays are so powerful, they are even capable of damaging the Warp Star's surface.
The monster itself can also heal damaged segments, unless attacked rapidly. The hot air balloon's engine allowed Kirby to become Jet Kirby, but as the kids quickly found out, the monster was capable of healing its damaged body parts, so Kirby had no choice but to withdraw the Jet ability. Thankfully, however, King Dedede dumbly shot a cannonball up there, which allowed Kirby to become Bomb Kirby and therefore easily be able to overpower the monster and destroy it along with the ozone hole, thus returning the abnormal weather back to normal.
The Ozone Hole Monster is a large, translucent, glowing serpentine creature with glowing purple eyes. Its body glows different colors - white, purple, and blue, and electrical surges flow around the monster's body. The monster, just like its name suggests, lives in a hole in the ozone layer.