|“||A sneaky, underhanded underworld figure, Heavy Mole will hit you when you least expect it.”|
|— The Cast of Characters • Kirby's Avalanche Instruction Booklet|
Heavy Mole is the boss of Yogurt Yard in Kirby's Adventure and its remake, and is one of the few mechanical bosses in the series. He is a monstrous robotic foe that spends all of his time digging tunnels beneath Dream Land. Unlike most bosses from Kirby's Adventure, Heavy Mole doesn't make an appearance in the anime in some form. However, there is another monster called Mole that has similar techniques and concept as Heavy Mole.
Heavy Mole, contrary to his name, does not resemble a regular mole. He is a shiny, brass, dome-shaped machine with two bright red retractable saws on the ends of him. He has a single, large eye and his golden, mechanical exterior is covered in gyrating spikes, which he uses to drive through the dirt that he resides in. The back of him can forcibly shoot out Dygclops as if they were missiles. He is also capable of flying low to the ground. This may be due to the fact that he has two small propellers on his back.
In Kirby's Adventure and its remake, Heavy Mole is entrusted with a piece of the fabled Star Rod when Nightmare invades the Fountain of Dreams. When the battle ensues, Heavy Mole digs through a large sea of dirt and will fire out Dygclops from behind him that Kirby can then inhale (the yellow ones give Hammer when swallowed, which can destroy the dirt in the battlefield, and the red ones give Sleep when swallowed). During the fight against Heavy Mole, the screen is always scrolling and focuses on him—so if Kirby gets off-screen, he automatically loses a life regardless of his remaining health.
|This section contains information that does not coincide with the main series canon.|
Later on in the series, Heavy Mole appears as one of the challengers faced in Kirby's Avalanche. He is the twelfth impediment in the game, and is faced after Paint Roller and before Mr. Shine & Mr. Bright. His dialogue with Kirby is below.
- Heavy Mole: "I am Heavy Mole, watch while I undermine your precious dream!!"
- Kirby: "You are sneaky, but I will not be distracted by your under-handed tactics."
The "heavy" part of Heavy Mole's name comes from his weighty, metal body. The "mole" part comes from Heavy Mole's ability to dig, just like the actual animal.
- Although Heavy Mole only made noteworthy appearances in Kirby's Adventure, Kirby: Nightmare in Dream Land, and Kirby's Avalanche, his red buzz saws are used as projectiles thrown by Moley and Mrs. Moley in later games. When these buzz saws are eaten, Kirby gets the Cutter ability.
- Heavy Mole appears as a collectible keychain in Kirby: Triple Deluxe, using its sprite from Kirby: Nightmare in Dream Land. The sprite is missing the small blades on its top, leaving two gaping holes in their place.
- In Kirby's Avalanche, his AI is used by Zoh Daimaoh in Puyo Puyo, however, unlike Zoh, he doesn't shake the board, but King Dedede does.
- Heavy Mole and Heavy Lobster are comparable in that they both have "heavy" in their names and look to be made of the same material. In addition, their names and appearance are both based around animals.