Zim: Overzealous, impulsive, and convinced of his own greatness, Zim is incompetent as an invader, yet dreams of pleasing his species' leaders, The Almighty Tallest, by taking part in Operation Impending Doom II, an Irken military initiative to conquer the universe. The Tallest, however, in a bid to be rid of Zim, send him to Earth (a planet of no interest to the Empire on the outskirts of the known universe) on a mission of conquest with a small ship and a robot servant cobbled together out of spare parts, expecting him to die or become lost en route. Against the odds Zim lands on Earth and establishes a base and, much to the chagrin of the Tallest, routine communication with his homeworld.

Because of his stature, Zim disguises himself as a human child. Despite his tendency to vociferously malign humans as a species, his undisguised green skin, a severe allergy to water, his refusal to eat human food, multiple failures in his disguise, and an occasionally blatant disregard for his own cover, no one realizes that Zim is an alien -- with the exception of Dib. In spite of his slight build, Zim occasionally displays superhuman strength and agility, although due to the show's lack of continuity, these traits are not always present. He is never without his PAK, a backpack-like piece of equipment with long, retractable arms that enable him to move about quickly and climb almost any obstacle. Zim constantly schemes to enslave or destroy mankind, and despite his access to potent Irken technology, his plans, frequently based on misconceptions, are never successful.

WOOO GO ZIM

lol he is pretty cool...though he is really dumb for an invader...

yeah, that's why I love him! XD stupidity is awesome! (*cough*someoneisbeingcompared*cough*)

lol..Gotta love him though...