Literature
Arbok Report
Arbok (the Cobra Pokémon) is an uncommon Poison-type Pokémon found among grassy fields within the Kanto, Johto, Kalos, Alola and Kitakami regions as well as the Sinnoh region on rare occasions. While they might not be among the most powerful of Poison-type Pokémon, Arbok are frightening creatures that can more than make life difficult for intermediate trainers in battle. Granted, their chest pattern might only work at frightening the young or inexperienced, but things will more than become an issue once your Pokémon gets constricted to the point of no return!
Ekans and Arbok are closely related to both rattlesnakes and co