Devil Kazuya (デビルカズヤ Debiru Kazuya), formerly simply known as Devil (デビル Debiru) is a character who made his debut in the original Tekken in the form of an unlockable third costume for Kazuya Mishima and his playable debut as a standalone character in Tekken 2 . Devil Kazuya is one of the main antagonists/anti-villains of the series. He is the cursed soul half of Kazuya Mishima and later Jin Kazama for inheriting the Hachijo Clan's cursed blood at their births. Originally a malevolent entity with the intent of possessing either Kazuya or Jin, one-half has merged with Kazuya.
Though there are supposedly multiple 'devils' within the series, only the entity which inhabited Kazuya is referred to as 'Devil'. He is the final boss for every character in Tekken 2 except for himself, if the player uses Devil then his final boss will be Angel. Devil can take his own form or can take over the body of Kazuya or Jin to become Devil Kazuya or Devil Jin respectively.