Prehistoric Piranha

The Prehistoric Piranha is a boss in the Wii video game Super Mario Galaxy. It is a mix between Petey Piranha and a dinosaur looking beast. It's one of the first bosses in the game, and will thus be rather easy to defeat compared to some of the others. At first it'll crawl around the stage in an egg, though Mario will be required to break the egg open in order to fight it. Following this, the Piranha Plant will be enraged, and will start to stomp around the planet. To kill it, Mario will have to spin attack its tail three times, where it'll then, oddly, explode, thus revealing that level's star.