Ryan Ochoa as Lanny - Brady and Boomer's evil cousin and next in line for the throne. He is the main antagonist of the series. He usually spends his time trying to think of ways to get rid of Brady and Boomer; and attempts to cause them trouble. He even attempted to have them both killed during the first episode so he can inherit the crown. He has a talking fish who advises on how best to foil the kings. He fell in love with the mermaid Amazonia in the episode "A Mermaid's Tail" even asking her to marry him. Surprisingly, neither Boomer nor Brady is aware of Lanny's evil intentions, thinking of him as either an minor pest or sometimes a friend, which aggravates Lanny even more.