Long ago the three Legendary Beasts, Raikou, Entei, and Suicune, were said to have passed away in a fire that took place in Ecreteak City’s Brass Tower. Ho-Oh, the Rainbow Pokemon, managed to revive the trio, though decided that it best to stay away from humans for a while. And so, like a phoenix rising from its own ashes (which is exactly what Ho-Oh is based off from), the three re-emerged from the tower and took off in different directions.
As the legend goes, the three creatures are supposed to be embodiments of what happened to the Brass Tower during that faithful night. And it all began with the lightening that started the fire . . . Raikou, the Thunder Pokemon, is the embodiment of that lightning. Quick to strike and mistrustful of humans, Raikou is most-likely based off from a tiger as it is large and agile. The purple ruff follows after it like a veil is very similar to cumulonimbus clouds, types of clouds that often go hand in hand with thunder storms. Raikou is the only member of the legendary beasts that does not have a weakness against one of the others (Entei is weak against Suicune and Suicune is weak against Raikou). Out of the three, Raikou has been given a more minor role. Ash didn’t encounter a Raikou until the thirteenth movie, while Entei and Suicune had both played major roles in the third and fourth movies, respectively.
After the lightning struck the Brass Tower, a flame was ignited. Entei, the Volcano Pokemon, is the embodiment of the fire that took place. Entei is based off from Chinese guardian lions that are a mix of male lions (the fur surrounding its neck) and short muzzled dogs. The structure of Entei’s face resembles that of a kabuto, a samurai helmet, and the puffy fur coming from its back resembles smoke that would rise out of volcanoes. In the third Pokemon movie an illusion of Entei played a large role in the movie’s plot and acted as a guardian for a young girl who missed her parents.
And then finally, after the lightning and the fire came the rain that put out the destruction. Suicune, the Aurora Pokemon, is supposed to be that rain. Unlike the other two beasts, Suicune has a much larger role in both the games and the anime. It’s the version mascot of Pokemon Crystal and is pursued throughout the anime, manga, Crystal, HeartGold and SoulSilver by Eusine, a friend of the gymleader Morty. In the fourth Pokemon movie, a Suicune played a major role in battling a controlled Celebi, and it also purified water. According to its pokédex entries, Suicune is said to be the reincarnation of the northern winds, graceful and otherworldly. It is compassionate and pure and is able to even cleanse water.
The order in which the Legendary Beasts are listed in the National Pokedex matches the order of events that took place at the Burned Tower. First the lightning that started that sparked a flame, next the fire that burned the tower down, and then finally the rain that quenched the flames and eventually put them out.