Ludwig

"Yes father, we're awaiting for your command."

Ludwig Von Koopa is one of the Koopalings. He's the oldest of them all and technically the self-proclaimed leader of the sibling gang. His look indicates that he's a serious and a mature Koopaling, but he's usually a show-off, as he has a quite mechanical genius which he can contain in himself and do serious inventions. He's also aware of the fact that he underestimates his enemies most of the time, but he also acknowledges his defeat whenever it's imminent, making him the most honorable. Mike Vaughn portrays his voice.

History
Ludwig Von Koopa first appeared in Super Mario Bros. 3, as the seventh boss, in Pipe Land. He also appeared in Super Mario World, and NSMB series as a recurring character.

He also appeared in spinoffs like his siblings, although having more personality in here than the mainline games.

In Prismverse Saga
Ludwig Von Koopa first appears in SMATSP as a mid-boss, alongside his siblings and assists Bowser Jr. in Bowser's Clown Car. After his defeat, he orders his siblings and tells Bowser Jr. to stand behind in their father's castle, to protect their home from any threat necessary.

His future appearances are unknown, but he'll appear individually as a boss in a future episode.

Trivia

 * Ludwig is named after the famous musician Ludwig Van Beethoven.
 * This fact is further revealed in the cutscene that plays out after his defeat in Super Mario World.
 * Iggy has the same voice actor as him.

Lore
Ludwig Von Koopa is one of the Koopalings. He's the eldest, the most mature and the most intelligent of them all. His past and his biological family are unknown, but it's known that he was adopted by Bowser when he just entered his teen years.

Unlike his siblings, Ludwig was not just trained to be a soldier, but also as a proper member of his father's society: By also learning how to play piano, creating new inventions and learning magic. He displayed marvelous talent in all, making him a potential heir to Bowser's throne someday. His genius was more chiseled and polished, unlike his brother Iggy, whose genius was more raw and open to new knowledge and possibilities.

As the eldest Koopaling, he was assigned to Pipe Land to take control. He had given quite a challenge to his adversaries, but he had sadly fallen in their hands. His later battles with them didn't end too well, but he was almost close to defeating them with his interesting setups of moving platforms and cloning ability, which was a rare magic ability taught to the most brilliant ones. He even created his own armada with a lot of minions by his side, indicating his perfect leadership and adaptability with most of Bowser's minions.

But there's still a long way to go for Ludwig if he wants to be by his father's side as a better Koopa, or even surpass him and be the new king. (Which doesn't seem to a great possibility anymore as Bowser Jr. has that great opportunity now) but he wants to help his father and his brother Bowser Jr. with any way he can when he becomes a great Koopa in heart and skill.