It has the Pressure ability which decreases the target's PP if they use that move on Raikou. It can also have Volt Absorb as its other ability if obtained from the Dream World.
Raikou is a tiger-like creature. It carries rainclouds on its back which let it fire Thunderbolts at will. It descends with the lightning, and races across the land barking a cry that shakes the ground and sounds like crashing thunder. While running it stores up static electricity, then shoots off the excess. It is also said to help other electric Pokémon if they are in danger.
In the anime
Raikou appears in the episode The Legend of Thunder!, where it's captured by Team Rocket and then saved by Jimmy and his Typhlosion.
The term "Legendary beasts" is the only technically correct term to refer to Entei and its companion legendaries, due to the fact that rather than having specifically canine or feline traits, all three of the trio share both.
Raikou somewhat resembles a saber-toothed cat because of its long fangs; and its stripes give it the attributes of a modern day tiger. Raikou is also partially based on the Japanese Thunder God, Raiju, who has been depicted in the forms of a tiger, monkey, cat, wolf, and weasel. It is said to have a roar like crashing thunder, as can be compared to the roar of a tiger, which can be heard from many miles away.
The first three letters in its name comes from the word Rai which means thunder or lightning in Japanese.
It is the only member of the Legendary Beasts to not appear in a movie from the Johto region, although it did appear in the anime. A shiny Raikou also appeared as a main character in the movie Zoroark: Master of Illusions.
It is the only one of the Legendary Beasts not to have a movie or game dedicated to them.
The main difference between Raikou and the other Legendary Beasts is that it has sharp claws, which it can't retract, whereas Suicune and Entei can retract theirs.
In Pokémon Gold and Silver the hair on its back is gold rather than purple as it is in every other game.