The Adventures of Rocky and Bullwinkle (2018)

S01E12 Moosebumps!: Chapter Three

Bullwinkle and Rocky embark on an adventure to a strange island rumored to be home to a variety of monsters, hoping to track down the elusive mad scientist who developed the serum that transformed Bullwinkle into a creature. However, their quest takes a turn when they discover the island is ruled by the formidable and fearsome monster known as Humongalon.