Grandfather (KND)

"Thanks for reawakening the pure evil. Now get out of my sight!"

- Grandfather

Grandfather is the main antagonist of Operation: Z.E.R.O.. He is a demonic being who ruled the world before being overthrown by his son Monty Uno. Many years later, he is revived by his son and successor Father and begins transforming the people of the world into Senior Citi-zombies. Grandfather is very tall and lanky, and significantly taller than a normal person. He has a bald head and a large beard with long, scraggly strands of hair. Despite making only one appearance, Grandfather is by far the most powerful and most evil villain in the series.

He was voiced by Neil Ross.

History
Long ago, Grandfather ruled the world and forced all children to work in his tapioca factories. One day, his son Monty Uno discovered the Book of KND and led an uprising of children, defeating his evil father, erasing his powers and memories.

Years later, Grandfather's other son, Benedict Uno, used the Recommissioning Module on Grandfather, now a decrepit old man, to restore his former self, expecting to work together with him to destroy the Kids Next Door and rule the world alongside him. Instead, Grandfather shuns his son and orders him to leave, calling him a failure and saying he liked his other son more.

He then revealed his plan: To turn all the kids in the world into Senior Citi-Zombies, as well as everyone who has ever been a kid. The villains cheer, until they realize that they all used to be children and that this amounts to every person in the world. They try to flee, but in vain; Grandfather turns all of them into his zombie minions and orders them to invade the Kids Next Door's treehouses throughout the world, turning them into zombies as well and turning the treehouses into tapioca factories. Soon, every nearly KND operative (and presumably every person) on the planet has been transformed, save for Numbuh 1, who would soon re-commission his father, Numbuh 0.

After establishing his rule over the world, Grandfather turns his efforts to finding and destroying the Book of KND, as it could provide children with hope; the only thing that could defeat him. He arrives near its location just in time to be confronted by his son Monty, who is carrying the book in his back pocket. Monty by wrestling with him until he found the Book of KND. He is able to resist Grandfather's power, but soon begins to succumb to it.

He is able to fight off Grandfather long enough for Sector V to launch the KND Moonbase at him, seemingly destroying him. However, Grandfather survives this relatively unscathed and emerges from the wreckage, only to find out that he is standing in a Decommissioning Chamber from the moon base. Grandfather and Numbuh 0 are then both decommissioned once again, turning them back into their harmless, clueless adult selves.

Powers
Grandfather has the ability to turn people into Senior Citizombies, monstrous, geriatric undead who can turn others into zombies as well, through touch. Although people turned into Senior Citizombies do retain a semblance of their personality, they invariably become the obedient minions of Grandfather and attempt to transform anyone they come in contact with. This power also affects inanimate objects, making them Victorian in appearance.

In addition, Grandfather possesses several other superpowers similar to his son, Father, such as control over fire, levitation and physical invulnerability. He also appears to be immortal while he has his powers since not even 39 gazillion tons of red hot metal and duct tape was able to crush him.

Trivia

 * Grandfather was reawakened using the Recommissioning Module, despite not being a member of the Kids Next Door. This also implies that he was defeated in the past by a decommissioning device, despite the KND (7th Age/Futuristic that is) not even existing prior to his defeat.
 * Operation: C.A.K.E.D.F.I.V.E. involves the Annoyingly Cute Triplets Who Lived Upon the Hill, who were enemies of the KND during the nineteenth century. Father refers to the mother of the ACTWLUH as his great grandmother, which would make her Grandfather's Grandmother and one of the triplets his mother. It is shown in Z.E.R.O. that Numbuh 0 was the founder of the 7th age of the KND and the 19th century was a totally different age.
 * Grandfather's overall design resembles that of Aku from Samurai Jack.
 * Grandfather's sons and grandson were among the only characters to never be turned into Senior Citizombies.
 * Numbuh 1 and Sector Z are the only people to be seen to be totally immune to Senior CitiZombification, because they were seen touching the zombies and remaining normal. This implies that they will be the future heirs to Grandfather's powers, though it is also possible they need to be touched by Grandfather himself to undergo the process.
 * In Operation: H.O.T.S.T.U.F.F., Numbuh 3 (although not a villain) who serves as the episode's main antagonist (and even parodies Regan McNeil) is seen to have fire-like powers similar to him although both are not even related. It is even notable that the latter is a lot more powerful than him.