I loved Dragon Warrior 7 for the psx. Has my favorite line from a video game. If I remember the lore right, the world was sealed to prevent evil from the previous game and it was one of the Maou, i forget which, left the hero island untouch so the hero could resurrect him and other time shenanigans to happen. Apparently all the games in the series is connect in a weird way.Giegue from Mother might be my favorite final boss in a game. The Mother series always asks you to use some form other than violence to deal with the final boss. I still think the way you deal with Giegue, by appealing to the humanity that had found its way into this inhuman creature, is one of my favorites.
Orgodemir from Dragon Quest VII is also a favorite final boss of mine. While he isn’t anything special necessarily on his own, I feel the themes of VII, and the fact that you’re more or less responsible for ‘creating’ the world again makes the fight with him very personal.
My favorite line is when Aira called the wind goddess a slut...