Ludwig Von Koopa

Ludwig Von Koopa (or Kooky von Koopa) is the oldest and supposed leader of the seven Koopalings, and a recurring antagonist in the Super Mario Bros series. He is traditionally the seventh and final Koopaling fought in most Mario games, with a few exceptions such as Super Mario World or Mario & Luigi: Superstar Saga.

Super Mario Bros. 3
Ludwig is the seventh Koopaling to be fought. Like his brother Roy, he causes a destructive earthquake when he lands. He must be jumped on three times to defeat him. Ludwig turned the king of Pipe Land into a Piranha Plant, but was defeated by Mario and Luigi in his airship, and ran off. In the SNES game Super Mario All Stars, which had remakes of all three NES games and lost levels of Super Mario Brothers, he turns the Pipe Land king into a dinosaur reminiscent of Yoshi.

Super Mario World
Ludwig is the fourth Koopaling to be fought, at the Twin Bridges. His fighting style is different from those of the other koopalings, but like all of them except Larry and Iggy, he must be jumped on three times to defeat him. He is fought in the biggest battle arena in the game, resembling a bridge above lava. Once defeated, he spirals into the distance and explodes in a puff of smoke.

Mario & Luigi: Superstar Saga
Like previously destroyed members of the Koopa Troop, Ludwig returned in another game. This time, however, he did not work for his father, Bowser, but the one possessing him: Cackletta. Like in Super Mario World, he was the fourth to fight Mario and Luigi, and was defeated. Afterwards, he apparently dies and disintegrates like the other defeated enemies.

Super Princess Peach
Ludwig was going to appear in Super Princess Peach (as were his siblings, except Bowser Jr.), but the decision was dropped, though after sprites were created for all of them.

New Super Mario Bros. Wii
For the first time, the Koopalings and Bowser Jr. appear together in a game. Like in Super Mario Bros. 3, Ludwig is the last Koopaling to be fought. Kamek uses his magic to make three platforms in the room rise, to which Ludwig's shell attack is not a threat (if Mario can jump to a different platform), Mario, Luigi, or the Toads will fall to their deaths if they fall off the platforms. It is Ludwig who falls over the edge when Mario jumps on him three times. Ironically, he survived what should have been a fatal fall, as he is seen in the ending sequence with Bowser, Bowser Jr., and the other Koopalings, though Bowser's castle falls on top of all of them.