King of the Koopas, and Mario's arch-nemesis.
Bowser Jr. is his son. The Koopalings, Iggy, Larry, Lemmy, Ludwig, Morton, Roy, and Wendy, were formerly considered to be his children as well, but this has been officially retconned by Miyamoto Shigeru since 2012.
Japanese name: Koopa
The following tags implicate this tag: baby_bowser (learn more).