When it was Yamakoshi's birthday and he tried to hit the piñata, the guard kept moving it above his head. In frustration, he tears off his blind fold, rips off the piñata and hits it until candy explodes out. The Riptides, island pranksters, are one of his worst enemies, hurting him physically and mentally since he was very small. They know his weakness and his strengths. His weakness is that he has had Yamakoshi ever since he was a toddler and loved him greatly. Going to extreme lengths such as trying to shut down the castle until Yamakoshi was found or demanding and shouting that the twins be thrown in jail and such. His most prized possession is Yamakoshi. The closest he ever came to murdering the kings was when he fired a cannon which missed by two inches from Brady's face. He thinks about ways to kill the kings before he sleeps. Lanny referred to the kings as Jamaicans. Only he is able hear Yamakoshi's voice and received him when he was 1. Yamakoshi is 100 years old according to No Kings Allowed. Women are fond of Lanny because he is small. As next in line for the throne, Lanny has a certain position of power, enough to be able to order some of the residents of Kinkow. Lanny is EXTREMELY rich as he was willing to reward the person who found Sirocco 1,000,000 dollars. Sirocco supposedbly broke free (Brady took off his mask) and Lanny offers one million dollars six more times making the kingdom much more rich then it has ever been. Lanny knows his island well. He was hated at one point when he was to collect money when the kings were broke for spending money for things such as golden toilet paper and rockets. He was booed at when he said anything, however he mentioned the million dollar reward and Kinkow cheered, he shooed them away calling them greedy peasants. Lanny's plan to foil Brady's scheme of stealing the mandatory money Lanny had gathered from the islanders almost worked with the interception of Mikayla. Lanny is shown to have bear pajamas which are to represent his fierce, predatory nature. A man starts to announce it but Lanny threatens to throw him in the dungeon if he does not stop. The man then runs away like a girl fearing for his life. Ryan Ochoa who plays Lanny states that in most films he plays the villain. Lanny does have a small sense of humor as he says that Blinking is not aloud in his video of the king's fight with Atog since they may miss it. Lanny then snorts and before the rematch he states that the kings can't get their dignity back since they've never had it. He also cracks many jokes, mostly offensive ones.
Lanny is power-hungry, cruel and arrogant, especially towards peasants and most people who know or even encounter Lanny gravely dislike him to a fault, a specific example would be the Makoola family who openly insult and physically abuse him. After his cousins, Brady and Boomer ruined any chance of him becoming King of Kinkow, Lanny became embittered and unscrupulous, believing himself so deserving of being king that he was willing to murder Brady, Boomer and later Boz to achieve his megalomaniacal delusions.
Because of his sadistic, arrogant and obnoxious nature, mostly everyone on Kinkow despise him, excluding the Kings whom treat him with genuine kindness but Lanny is too resentful and obsessed, and constantly tries to kill and usurp their position to acknowledge this. The Kings stupidity are cause of their ignorance to Lannys evil nature and he constantly manipulates this to his own advantage. He also thinly hides his hatred towards the Kings with either morbid, passive-aggressive insults or relinquishing anger by punching two dummies with Boomer and Boz's faces stapled to them. Whereas Brady and Boomer are flawed rulers but do care for the good of Kinkow, Lanny is motivated purely by self-interest and should he have become king, he would become a tyrant amongst his people. This is displayed, after believing the Kings to be dead he instantly abuses his power by sentencing several peasants to imprisonment and even death for ridiculous reasons.
His sense of self-preservation at times exceeds his need for self-entitlement. For example after officially becoming king of Kinkow then being kidnapped by Zadoc, before he was about to be killed he transfers power back to Brady and Boomer, saving himself in the process. He also didn't seem to care that Kinkow was about to be destroyed by the resurrected King Kalakai, and instead assists him in helping destroy the Light Side, presumably out of fear of his life although there is the offside chance that Kalakai did promise him a position of power on the Dark Side.
The only other thing Lanny has any regard for is his pet fish, Yamakoshi whom he does seem to care for, even if the two argue and frequently insult each other. Lanny also appears to be the only human who can understand Yamakoshi, as well the only one who can speak to him. He went as far to throw Yamakoshi a one hundredth surprise party and was saddened over his supposed death and later overjoyed on his later return. There has been evidence that Lanny's deceitful and cruel nature was cause of Yamakoshi, who influenced him negatively to do evil and kill Brady and Boomer. In a flashback to Lannys' childhood it's shown Yamakoshi told him to kill the Kings and take their position, it's also important to note that Yamakoshi is responsible for many of Lannys' villainous schemes. It's unknown what happened to his pet fish after Season 2 as he was not mentioned or seen throughout Season 3.
Lannys' megalomania seemed to have unfettered around Season 3 after becoming king of his own personal island, Lanada. Instead of either murdering the Kings and taking control of Kinkow he instead attempts to drive the peasants into Lanada so he could rule them. He appears less cunning and more comedic, and resorts to petty theft from gold to a wheel of cheese.