Bowser (Japanese: クッパ, Kuppa, "Koopa"), also known as King Bowser or King Koopa, is a fictional character and the main antagonist of Nintendo's Mario franchise. In Japan, he is titled Daimaō (大魔王, "Great Demon King"). He is the arch-nemesis of the plumber Mario and the leader of the turtle-like Koopa race. Bowser's defining traits include his monstrous appearance with dragon-like elements, full-throated roar, fire-breathing abilities, and tyrannical personality.
https://en.wikipedia.org/wiki/Bowser