The Final Boss of the very first Dragon Quest game is the Dragonlord. Before the game starts, he stole the Ball of Light to conceal the kingdom of Alefgard in a veil of darkness. That all came to an end when the descendant of Erdrick came to Charlock Castle and defeated him in battle.
The Final Boss of Dragon Quest II is Malroth. After the death of the evil sorcerer Hargon, this Demon Lord rises to finish off the Heroes and make sure evil conquers all.
The Final Boss of Dragon Quest III is Zoma. Having traveled to Alefgard after the defeat of the Baramos, the party confronts his master and vanquish with the Ball of Light, thus setting the stage for the other games in the Erdrick trilogy.
The Final Boss of Dragon Quest IV is Necrosaro. The demonic transformation of the game's main villain, Saro, this devil is obsessed with unleashing the power of Esturk and making it his own.
DQ4 Remake
The Final Boss in the remake of Dragon Quest IV is Radimvice, an evil High Priest and assistant to Saro.
The Final Boss in Dragon Quest V is Mildrath. He is known as the lord of evil and has imprisoned the Hero's mother in the Demon World, waiting for the Legendary Hero to arrive.
The Final Boss in Dragon Quest VI is Deathtamoor. After two confrontations with the party in separate forms, the Demon King sheds his body apart and attacks with his head and hands. However, even after becoming more powerful, Deathtamoor is still no match for the Hero and his party. Everyone soon rejoices the heroes' victory over the evil Devil lord.
The Final Boss in Dragon Quest VII is Orgodemir. After being revealed for impersonating God, the Demon Lord escapes into the Dark Palace awaiting his enemies in the throne room. Upon his ultimate defeat, Orgodemir curses God and all those who follow him and disintegrates.
The Final Boss in Dragon Quest VIII is Lord Rhapthorne. After his first defeat, Rhapthorne transforms into a stronger being: a large devil looming over the land. However, his reign of terror wouldn't live long enough as he is defeated by the party.
The Final Boss in Dragon Quest IX is Corvus in his demonic state. he is the one who ressurected the Gittish Empire so he could destroy the mortals of the Protectorate.
