Ludwig von Koopa

Ludwig von Koopa is the leader, eldest and smartest of the Koopalings, a group composed of seven siblings who lead the Koopa Troop. He is often ignored by Bowser Jr. when he tries to explain important things about combat.

Super Mario Advance 4: Super Mario Bros 3
In Super Mario Bros. 3, Ludwig and his siblings were sent by Bowser to the cause havoc in the Mushroom World. Ludwig decided to raid the Pipe Maze; when he got there, he attacked a Toad that was the King's attendent, stole the magic wand and transformed the Pipe Maze's King into a green Yoshi. Mario and Luigi arrived in the Pipe Maze to help. After the Bros. go all through the Airship, they fight Ludwig in his cabin; the Koopaling lost the fight and the Bros. returned the King to normal.

Super Mario Advance 2: Super Mario World
In Super Mario World, Ludwig, his siblings, and Bowser invaded Dinosaur Land as retaliation for the latter's short-lived imprisionment in a book by Yoshi. They trapped the Yoshis inside eggs, captured the actual Yoshi Eggs, hypnotized Reznors, and built six castles across the territory, with the seventh and eighth having been built in a cave which became the Koopa Troop's main base of operations, the Valley of Bowser. After Mario and Luigi go all through the fourth castle, they face Ludwig in his room; the Koopaling lost the battle and the Bros. rescued one of the Yoshi Eggs, along with destroying the castle, ending Ludwig's days of composing symphonies there.

Personality
Ludwig is a mature, quick thinker who's quite good at lying, negotiating, and managing tricky situations. He thinks of himself as the leader of the Koopalings, but the others disagree with this statement. Despite this, he's seen leading the discussion over the blorbs' cure, he's the captain of the Koopaling squad in Mario & Luigi: Superstar Saga + Bowser's Minions, suggesting he's, in fact, their leader, regardless of what the others say.

He's highly intelligent, as he was able to trick the Best Fitness Friends into thinking he was Beef, he built the Super Ludship and the Super Ludsub etc. When he gets mad due to someone else's actions, he seems to quickly resort to insulting whoever was responsible for doing that and vows revenge. He has a big ego and sometimes refers to himself as "the Great Ludwig", especially when he's annoyed. He's musically inclined and can be quite dramatic at times. He seemingly owns a company called "Ludwig Painting", implying he's interested on this type of thing.