Kingfin appeared in 2007 video game called Super Mario Galaxy. Kingfin is a boss in Super Mario Galaxy. In the Prima Games guide, an issue of Nintendo Power, and in his Super Mario Galaxy trading card, he is called "the Bonefin", possibly because the name of its galaxy is Bonefin Galaxy. His name is most likely a pun on the word "kingpin", which refers to the most important person in an undertaking or organization, such as a galaxy boss. Kingfin commands a legion of Skeletal Fish Guards and is himself a colossal skeletal shark, although in actuality, sharks are cartilaginous and do not have bones. Kingfin also has beams of light shining out of his eyes when battling Mario. However, if the player uses Luigi, his eyes do not shine. Through a simple glitch, the eyes won't shine if the player uses Mario, when the player bothers Luigi in the Observatory (spinning at his proximity/jumping on him for example) before entering the Bonefin Galaxy.
In battle, Kingfin has the power to summon large hoards of angry Skeletal Fish Guards from the craters in the center of the planet, which attack in the same way as Torpedo Teds, homing in on the player from all directions. The more damage Kingfin takes, the more guards he will summon to attack Mario. The theme music in the battle with Kingfin is the same with Bouldergeist. However, when Mario or Luigi comes closer to Kingfin, a percussion beat is added to the background music. The music speeds up once Kingfin has taken damage three times.