In the last area of the Gujing dead end in "Metaphorical Fantasy: ReFantazio", you will encounter the bottom BOSS, and this BOSS has almost no obvious weaknesses. If you want to fight, you can hit his two eyes with a thrust attack. Try it. Master of double swordsmanship + an archer.
How to defeat the BOSS in the dead-end fantasy ancient well
July 8, daytime, explore the dead end of the ancient well and the decaying waterway 05/06. There is only one treasure chest, Treasure Chest 52, which contains ambrosia.
Going forward in the plot, the boss has no weaknesses, but its two eyes are weak to attack.
You can try Double Sword Master + a shooter. The shooter will attack the physical weakness, and the Double Sword Master will directly kill you with super physical weakness.
