In Dragon Quest 3 HD-2D Remake, players have to be prepared to take on the Lord of the Underworld, Zoma, as the final boss of the main game. This boss fight is the hardest battle the game has thrown at the player thus far, meaning their party should be well leveled and equipped to match. While this fight is technically the final boss, the game is not over once Zoma is defeated, meaning players have even more of an incentive to become as strong as possible.

https://screenrant.com/dragon-quest-3-hd2d-how-to-beat-zoma-boss-guide/