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.
In Pokémon FireRed and LeafGreen, Raikou roams around Kanto if the player character's Starter Pokémon was Squirtle and they have beaten the Elite 4. In FireRed and LeafGreen, it is very hard to catch because it will flee unless your Pokémon out has the ability Shadow Tag. It appears at Level 50.
In Pokémon HeartGold and SoulSilver, the player could get a Shiny Raikou at Gamestop on January 31 through February 6, 2011, which later was given out via Wi-Fi in late February 2011. You can also get it at Kanto Route 25, then the Burned Tower. It appears at Level 40 at both Route 25 and the Burned Tower.
Raikou is a tiger-like creature. It carries rain clouds 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.