Harley's Humongous Adventure (JP: Kagakusha Harley no Haran Banjou) is a SNES platformer from Visual Concepts. An inventor accidentally shrinks himself and must make his way through his house, now enormous and full of danger, to restore his original size. It was released in the US and Japan only.
Hip young scientist Harley loves inventing things in his attic lab. He's already made a jetpack and his latest invention is a machine that shrinks things. Unfortunately something goes wrong and Harley is shrunk down and the machine explodes. Now Harley must make his way through his house, collecting the parts of the machine so that he can return to normal.
The game is a traditional side scrolling platformer. Harley must make his way through each level to collect a piece of his shrinking machine at the end. Since Harley is small now, enemies consist of bugs, rodents and common household objects like rolling cans and bouncing rubber balls. Harley's biggest threat is a giant mutated rat that Harley faces off against multiple times. Harley has a number of different weapons at his disposal to fight off these enemies including nails, tacks, marbles, rubber bands and firecrackers. Harley can also collect items to help him like insecticide that grants him temporary immunity, jetpack fuel which he can use to fly, a parachute to survive high falls and air supplies that Harley uses to explore water filled pipes. Starting in his lab, Harley must make his way through the kitchen, bathroom, toy room (where Harley takes control of a toy tank) and the attic.
The game is notable for its unique mixture of pixel art and digitized claymation. All of the clay effects were created by A-OK Animation who also worked on Claymates.