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Iggy Koopa is one of the eight children of Bowser, of which, he is the fifth oldest;Physical Description
Iggy is known to have a rainbow mohawk with the colors red, yellow, blue in a pattern. His mohawk resembles his brother Lemmy's hair except his looks more straight, less messy, and pointed upward. He is shown to have thick glasses with swirls on them, though some art depicts him with blue eyes. But the difference of his eyes might just because of his emotions. Strangely it is unknown how he wears glasses because he (or other species of koopas) have never been depicted with ears. He also seems to be one of the smaller Koopalings. He also has four visibile fangs in the upper corners of both sides of his snout. Personality
Iggy is portrayed as being a mechanical genius, having invented various machines used by the Koopa Troop, most notably the mechs used by his siblings in Yoshi's Safari. He known by many as the second smartest, only being beaten by Ludwig. It is also rumored he is constantly being Bullied by his older brother Roy Koopa.Many assume his hobby is inventing things for the Koopa Troop. Also, according to in-game dialogue in Super Mario World, Iggy is also demented, essentially making him a mad genius. In Mario is Missing!, Iggy spoke completely in rhyme. In the comics he seemed to think his father was somewhat stupid and acted like he was smarter.
In The Adventures of Super Mario Bros. 3 and Super Mario World, Hop was quite childish in personality, and often pulled pranks instead of causing true crimes, though some episodes had him doing so.
In the Super Mario Amada Series, Nintendo Comics System and Super Mario Adventures, Iggy's personality was largely identical to that of his brothers, with him having no real defining characteristics. History
----------Super Mario Bros 3
--Iggy's first appearance was in Super Mario Bros. 3, in which he aids his siblings and father in their plot to conquer all of the Mushroom World. Using his army and weaponry, Iggy took control of Giant Land, the rightful king of which, he turned into a dinosaur (or a Donkey Kong Jr. look-alike in remakes) using his own stolen Magic Scepter. Super Mario World
--Sometime after the events of Super Mario Bros. 3, Iggy returned with his family in Super Mario World, aiding them in their conquest of Dinosaur Land. When Dinosaur Land was successfully subjugated by Bowser's forces, Iggy was given reign over Yoshi's Island, in a castle where he guarded a Yoshi trapped within an egg. Mario is Missing!
--Though absent from the NES version of Mario is Missing!, Iggy is in the SNES and PC versions of the game, the latter of which he spoke entirely in rhyme. In this game, Iggy travels to Antarctica with his family and some of his siblings, trying to aid them in stealing artifacts, which Bowser intended to sell in order to raise funds to buy hairdryers from Hafta Havit Mail-Order; with these hairdryers, Bowser planned to melt Antarctica, flooding the Earth. Yoshi's Safari
--In Yoshi's Safari, Iggy helped his family invade the kingdom of Jewelry Land; stealing the jewels that that maintained the stability in Jewelry Land, Bowser entrusted one of these jewels to Iggy, who was given domain over Grand Bridge. To aid his family in the conquest of Jewelry Land, Iggy created seven heavily armed mechs, one for himself and the other six for his brothers and sister. His mech resembled a giant Blooper. Hotel Mario
--In Hotel Mario, Iggy, unlike his siblings, did not gain a hotel when the Mushroom Kingdom was taken over by Bowser; instead, Iggy was located inside Bowser's Seizure Palace Hotel, in "Bowser's BBQ Room". In his battle against Mario in Hotel Mario, Iggy wore an oversized Bowser mask and, along with jumping between floors, could spit fireballs and summon a small amount of lightning that could strike Mario.Mario & Luigi: Superstar Saga
--Iggy's most recent appearance has been in Mario & Luigi: Superstar Saga, where he, along with his siblings (excluding the recently introduced Bowser Jr.) were employed by Bowletta to protect Bowser's Castle, which was converted into a flying fortress used to attack Beanbean Castle Town, from Mario and Luigi. Iggy is the first of the Koopalings encountered by Mario and Luigi, and before battling the two, Iggy will spin rapidly, making Mario and Luigi dizzy before fleeing further into his room. Mario and Luigi would need to dizzily stumble through the traps in Iggy's room to reach bespectacled Koopa and fight him.Super Mario Sunshine
--In Super Mario Sunshine, Iggy makes a small cameo appearance, being shown on a small screen battling Mario in Super Mario World, near the start of the game, where Mario is scanned by FLUDD.Super Mario Amada Series
--In the Super Mario Amada Series, Iggy and his siblings appear in the series' first story, Momotarō, where they aid Bowser in kidnapping Princess Peach. Iggy also appears in the series' third story, once again aiding Bowser, reimagined as the Wicked Queen, in his plot. Mario Cartoons
--In The Adventures of Super Mario Bros. 3 and Super Mario World, Iggy was renamed Hop Koopa and he, along with his twin, Hip Koopa, were portrayed as the youngest of the Koopalings. Unlike some of the other cartoon Koopalings, Hop closely resembled his game artwork. Hop and Hip were constantly seen together, and the duo were constantly pulling pranks on unsuspecting citizens of the Mushroom Kingdom. Like many stereotypical twins, Hop and Hip would often share their sentences by either speaking in unison or finishing each other's lines. Additionally, Hop was not portrayed as an inventor like in the games; that role went to Kooky.
Bio from "The Adventures of Super Mario Bros. 3 writers Bible:" While the rest of the Koopalings are in their teens, Hip and Hop are bratty six-year-olds. These twins don't go anywhere without one another, and are always finishing each other's sentences. Silly and dumb, goofy and bumbling, they are always lost, and have probably forgotten where they were going anyway. They flunked Koopergarten. They wouldn't be a threat to the Marios and the princess, if it weren't for the fact that they have the most powerful Magic Wands, and are easily manipulated by Bully and their other siblings. Super Mario Bros. Movie
--In the Super Mario Bros. movie, Iggy is not Bowser's son but his cousin. Iggy is much different from other portrayals, he is often seen with his cousin Spike, and acts as the brains of the duo. Later, Iggy and Spike become allies of Mario and Luigi.Publications
--Iggy appeared in both Nintendo Comics System and Nintendo Adventure Books, the latter of which first displayed his habit of inventing things, such as the Monster Mixer or the GLOM. Iggy also appears in Super Mario Adventures as do his brothers and sister, who act as Bowser's henchmen in his plot to kidnap and marry Princess Toadstool.
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