From the Super Mario Wiki
Corporal Paraplonk is a red-shelled Koopa Paratroopa who wears green shoes and a red bucket on his head. He is one of Bowser's minions in Mario & Luigi: Bowser's Inside Story, Mario & Luigi: Dream Team and Mario & Luigi: Superstar Saga + Bowser's Minions. He is usually seen in the company of Private Goomp and Sergeant Guy. In Mario & Luigi: Dream Team, it is revealed that the trio dream of one day bossing around Kamek and Bowser.
Mario & Luigi: Bowser's Inside Story / Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey
He is first seen with Private Goomp and Sergeant Guy in Dimble Wood. After meeting up with Bowser, the trio launch a Banzai Bill at Bowser's Castle, which was occupied by Fawful. When the castle retaliates, Bowser faces it in his giant form, at which point Paraplonk flies up and teaches Bowser how to attack.
Later, at the safe underneath Bowser's Castle, Corporal Paraplonk and his companions help Bowser locate the safe that holds the Star Cure that the Koopa King is after. However, when Bowser opens the safe, the three push Bowser inside, revealing that they had been bribed by Fawful since he last saw them.
Corporal Paraplonk was seen again right after the closing credits, where the minions ask Bowser for forgiveness. Granting it, he then orders them to resume their duties and help repair the castle.
Corporal Paraplonk reappears in Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey, reprising his role in the main game, while appearing as an enemy and a recruitable ally in Bowser Jr.'s side story. He fights alongside other Koopa Troopas and fights again alongside Private Goomp and Sergeant Guy where he is the First officer. In the post-game of the story, it was revealed that while Bowser pardoned him and his comrades of their treason against him, the rest of the Koopa Troop has yet to forgive them and even shunned them, citing they have to "earn back [their] trust," and Bowser Jr. believes their treason was due to being under the influence of the Malatone Formula:X earlier.
Mario & Luigi: Dream Team
In Mario & Luigi: Dream Team, it is revealed that Corporal Paraplonk was promoted along with his associates to Bowser's Royal Guard. His bucket is now black in color with a Bowser emblem on it. They travel with Bowser to Pi'illo Island to find Princess Peach. Corporal Paraplonk helps Kamek disguise as Princess Peach forming a lower section of the disguise. The trio are also fought in a boss battle as the Elite Trio.
After their defeat, Kamek demotes Paraplonk and the others to janitors and sends them back to the castle. After Bowser himself is defeated, he and his minions leave Pi'illo Island. While angry at his loss, Bowser blames Antasma and merely states that Corporal Paraplonk, Private Goomp and Sergeant Guy did pretty good by their usual standards, much to their joy.
Mario & Luigi: Superstar Saga + Bowser's Minions
Corporal Paraplonk returns in Mario & Luigi: Superstar Saga + Bowser's Minions. He is encountered twice and can be recruited after the second fight. He is a flying unit and is the second of the trio to be recruited. Corporal Paraplonk's special skill, Cranium Crunch, allows him to attack an enemy twice from above. Due to the bucket on his head, he has high defense. When battling Corporal Paraplonk, he can use the Shell Shock captain command.
Profiles and statistics
Mario & Luigi: Dream Team
Mario & Luigi: Superstar Saga + Bowser's Minions / Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey
Names in other languages