King Bowser Koopa (Japanese 大魔王クッパ Daimaō Kuppa "Great Demon King Koopa", in English also Lord Bowser, King Koopa commonly in other media) is the main antagonist of the Mario series and the King of the Koopas. He has repeatedly kidnapped or attempted to kidnap Princess Peach and take over the Mushroom Kingdom. He has on other occasions attempted to conquer the entire Mushroom World, as well as the entire universe. Despite his villainous nature, he has on occasion helped the heroes of the Mushroom Kingdom against common threats and participates with them in their numerous sporting events in spin-off games.
Since his debut, Bowser has been in nearly every Mario game, including the main series, spin-offs, and crossovers. Due to his role as the primary villain of the Mario series, he is mostly the final or penultimate boss in his appearances, if not as the main antagonist (an example being Mario and Luigi: Superstar Saga). In the Mario RPGs, Bowser is generally cast as an anti-hero or a minor villain, with the exception of Paper Mario and Paper Mario: Sticker Star.