While not the real final boss, Grigori had an awesome build up to him.
>comes to your peaceful village to wreck shit up
>you are the only guy, but at lvl 1 and with a shit sword you do almost no damage to one of his many health bars
>he chuckles and steals your heart
>tells you that you have to defeat him, if you want to recover your heart
>you train hard, fighting all manners of beasts, from hydras, cyclops, griffons
>there's also a cult dedicated to the dragon, that you fight against
>they manage to invade a giant fortress
>so you go and take it back
>defeat all the minions and are about to face the leader of the cult
>suddenly the dragon appears and kills the cult leader, telling the player that the cult has nothing to do with this
>that the player has to defeat the dragon to stop all this
>he destroys the fortress effortlessly, steals your waifu to motivate you in fighting him
>you finally reach his place and he starts talking about free will and destines
>he offers you a choice, let him kill your waifu and he will leave the land in peace, as the "vanquisher of the dragon" the player will become king just like the current king did
>or you can face him, risking oblivion
>you defeat him, and reclaim your heart back
>the end of the world has come, as a consequence of the dragon dying