Kaminari is based on the Japanese thunder god Raijin (雷神), and as such is physically modeled after him as well. He big and portly with red skin and pointy ears. He has wild black hair and a beard. He has two horns on top of his head and two big bottom teeth protruding from his mouth. He wears a headband and a tiger striped loincloth. On his back is a large ring with several drums on it. In some panels of the original manga he has as many as eight drums, while in others he only has seven or six.
Kaminari's personality varies depending on the series he's portrayed. Usually he is not an evil yokai but is frequently angered and grows hostile as a result of human experiments on clouds, rain and lightning, that happen to be conducted on his vicinity of which Kaninari takes offense, causing Kaminari to typically respond with violence. He can at times, however, calm down and reach agreements.
On the sixth anime he's far more self-centered as he wants to make humans respect him (through fear) like they used to during older times. He sides with Nezumi-Otoko's scheme purely to gain this respect, even if the populace at large considers him nothing but a character rather than a real supernatural entity. When he doesn't get the respect he wants, he immediately resorts to indiscriminate aggression purely to make humans fear him once more.
In nearly every instance, Kaminari is proud of his lightning knowing how powerful it is and tends to use it in all its glory. This often backfires on him when Kitaro redirects it back at him, often to his full demise, which implies Kaminari is excessively confident on his power's self-perceived omnipotency.
Shonen Magazine/Learning magazine
Kaminari lives in a large floating rock in the sky, but frequent artificial rain experiments conducted near his home angered him. When Professor Ameyama goes to investigate, Kaminari crashes his helicopter onto the rock and held him hostage. When Kitarō and Konaki-Jijii arrive to stop him, Konaki-Jijii weighs him down and forces him off the rock and onto the ground. When the rock comes down to the surface, Kaminari tries to destroy Kitarō with his electric powers, but Kitarō absorbs the electricity and fires it back, destroying him.
In the learning magazine version of the story, Kaminari was crashing airplanes in order to monopolize the skies. Like in the Shonen Magazine version, he tries to kill Kitarō with his electric powers, but this time he wastes so much power that he becomes very thin. Embarrassed, he hurries back into his rock.
He appears in episode #25 of the first anime adaptation, Electric Yōkai. In this episode, the artificial rain experiments started over a year ago, and Kaminari retaliated by preventing it from raining over a mountain village for the last year. After Kaminari crashes Ameyama's helicopter, the lab sends some fighter jets to the floating rock, but Kamianri shoots them all down. From there the story pretty much follows the Shonen Magazine version.
He appears in episode #23 of the third anime adaptation, Electric Yōkai Kaminari. In this episode, Kaminari is angry at Professor Ameyama for his experiments on harnessing lightning to make electricity. The experiments have left very little electricity in the sky to power him, but once Nezumi-Otoko brings him to a city with plenty of electricity, he goes on a rampage and abducts Ameyama. When Konaki-Jijii tries to weigh him down, Kaminari back into Ameyama's experimental satellite Electric 2 and absorbs so much electricity that he grows giant. He is brought back to his normal size by an invention of Ameyama's that absorbs electricity as it is struck by it. Though Kitarō still defeats Kaminari by absorbing and returning his electricity, in this version Kaminari survives and admits defeat. Afterwards, he reconciles with Ameyama and the two discuss how to balance nature and science over a cup of sake.
He appears in episode #32 of the 4th anime adaptation, Electric Yōkai Kaminari!. In this episode, a scientist fires a survey missile into the cumulonimbus cloud Kaminari's rock is hidden in. Kaminari retaliates by crashing the scientist's helicopter and abducts him. He then goes on a spree, striking lightning on anyone disrespecting nature and abducting them. From there the story pretty much follows the original Shonen Magazine story, with the exception that Kaminari survives the fight. After Medama-Oyaji scolds the scientist, Kaminari accepts that the humans have learned their lesson and is willingly transported back to his rock by Ittan-Momen.
He appears in the fifth episode of the sixth anime adaptation, The Electric Yōkai Disaster. In this episode, Kaminari appears after mistaking Nezumi-Otoko's call for god (Kami-sama) as a call for himself. Like the 4th anime adaption, he desires respect. A mob boss named Mr. Ameyama and Nezumi-Otoko use Kaminari to create the BiBiBi Electric Company, a company that cheaply sold electricity. With the profits, they paid off the city council, and Mr. Ameyama became the mayor. When a magazine reporter by the name of Yuriko Igarashi (五十嵐ゆり子) made a report on the company's bribery and tax evasion, Mr. Ameyama and Kaminari took action on their own. When Nezumi-Otoko found out that they killed Yuriko using Kaminari's electricity, he knew that Kitaro would get involved. Kaminari was pleased with the respect he received from providing the cheap electricity, but after the humans stood against him despite this, he decided to garner human respect through fear.
Kitaro eventually arrives and defeats Kaminari by draining his electricity and using a retaliatory Internal Electricity, like the original Shonen Magazine story.
Control of Electricity: Kaminari can freely control thunder and lightning. The drums on his back act as storage batteries and he beats on them to add to his electric power. In the 3rd anime, if he takes in enough electricity he can become giant and gains the ability to fly and breathed red lightning from the mouth. In the 4th anime he can fly by riding clouds. In the six anime, he shaped electricity into a multi-headed dragon.