Im have an issue with this boss, i tried everything but im unable to kill him, is there some trick or something?
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Not a trick as far as I can tell. I struggled with that fight aswell to be fair, it was a bit of RNG and using all my tools and consumables that could help at the time.
May I ask about your current build?
Also I'd advice to get the 'Holy Blow' Miracle for Priestess as soon as you have the spare change to buy it at the Church.
It costs 2 Mana, but it can deal easily around 15-20 damage, depending on how high the Faith of your Priestess is. (in general I think one should focus on Faith and Intelligence with her as I think you get the most milage out of her this way).
Also since I dont know what skills or spells you got (it's always good to get the MC/Protagonist/Jimmy at least the Fire Arrow spell in my opinion as it CAN deal a lot of damage, though without intelligence or mag attack stuff it can vary wildly), so here's a bit of advice regarding his default skills:
Encourage - not nessecary, dont use it, waste of your turn
Shieldbash - in my opinion it only seems to work with substantially weaker opponents anyways where maxing damage is usually more usefull than having a CHANCE to stun them - not to mention that with this opponent who is litterally a flesh-collosus twice the size of Jimmy, it just doesnt seem to work so dont bother.
Shield up - eh, dont bother, since it basicly just increases your chance not to get hit a little bit and reduces damage only by a bit either it's usually a waste of a turn, especially since the MC is most likely your main way of dealing damage, unless you got Holy Blow or have taken Priestess' build into a very creative direction.
Strike - not great, not terrible, your regular damage x 1.5 I believe is roughly what you get for it, which isnt GREAT but in a fight of life or death and with a way to replenish your Fatigue afterwards it's the best deal you got in your regular chest.
Of course if you still have your beginner sword at this point you WILL have some serious trouble.
Unless you went/go for a creative Dexterity/Agility built with high evasion (which in my opinion is a bad idea due to how the hit and evade mechanic works), you will most likely want to go for a longsword as it provides decent damage and while it causes a bit more fatigue it's well worth it until you get something better past the Titan Steps.
Other than that... dont bother with Torches. In a pinch a Sleep Potion or the like can help. Keep in mind that Priestess if she is out of Mana, can also utilize Herbs and Potions and use them on Jimmy/MC rather than herself. This should help you keep in the fight longer. It's primarily a test of endurance and damage...
In the worst case if your next oldest safe isnt too long ago it might be wise to go for it instead.
Hope this helps
