Koopabiza
The title of this article is official, but it comes from a non-English source. If an acceptable English source is found, then the article should be moved to its appropriate title.
Koopabiza is an island appearing only in the Club Nintendo comic "Super Mario: Erholung? Nein, danke!" In this story, Mario, Princess Peach, Yoshi and Luigi take a vacation to Koopabiza. It seems to be a typical tourist location, however, Mario and his friends are deeply disappointed about their vacation. The only known place on Koopabiza is the Gumba Royal Hotel. Bowser and Morton Koopa Jr. work on the island. The name Koopabiza is a pun on Koopa and Ibiza, an island in Spain and a popular tourist destination on Earth.
Koopabiza seems to be popular especially among Mario's enemies (hence the name), as besides Bowser and Morton Koopa Jr., also Wario, Koopa Troopas, Goombas, Lemmy Koopa, Wendy O. Koopa, a Sumo Bro, a Lakitu, a robe-less Magikoopa and an Urchin can be seen in the comic. There are also characters resembling Spikes, Boom Booms and Chargin' Chucks.