OK OK....hear me out:
I am actually playing a intelligence/dex build and have been toying with it for a while so here are my thoughts:
1) do not cast spells...at all ever...this is not your place. you will not deal enough damage even with 40 intelligence because you will not have the rings etc...and if you do, you will not have the setup to use your weapons (not enough stamina, not enough poise, damage absorption etc). You use intelligence only as an extra source of damage for your weapons...not to cast spells (although you can for PvE for invisibility, frozen mist, pestilent mercury etc...) but not in Pvp
2) use the greatsword of judgment, the aquamarine dagger, the Friede greatscythe primarily. Moon crescent sword and sage rapier are fun as well...matter of preference. of course you can use all other weapons than scale off dexterity like katanas sellsword etc...buff them with magic weapons if you want to use a spell buff or just resin...this is a hybrid build...I switch to any weapon my opponent uses generally just for fun as they are pretty much all +9 anyways...with 26/40 you can use any weapon apart from some pure strength ones....so use it!
Frayed blade require 40 dex...the rest (strength and int and faith) scaling are totally irrelevant. it is pretty much a prure dex weapon that will not benefit from your intelligence. but it is still the top katana for ease of use (chaos blade and other stance katanas are still top tier in proper hands).
3) here is the build at 125https://soulsplanner.com/darksouls3/27574
it is a hybrid build meaning it is stats hungry therefore needs the prisoner to optimize stats.
you need strength for the jusdgment sword, not the rest so you can save on strength if you do not wish to use this beautiful sword but you will miss out on the big big damage dealer of int hybrid builds. do not let the damage split fool you: with those stats, you out damage any GS and most UGS actually (buffed of course)
I use primarily the GSoJ for massive damage, laser mind **** (must use unlocked) and dealing with people that can be poise broken and little pesky weapons like SS and katanas
Friede is for the dagger quick step spammers and the backstab fishers that roll towards your buttocks all the time: weapon art has little poise but enough to guarantee trade win for these
aquamarine dagger is for the roll away spammers / kitters thanks to the combo r1 ==> L2 ==> R2 ==> R2
manikin claws I use to chase casters and pressure them to death... I use it mostly as a spear really but this is just me because they are my favorite weapons but this is my unique playstyle mixing reverse back steps with everything so...can use a small shield intead whatever....and armor etc is also up to preferences obviously.
now if you want a sorcerer build, look not at this but use crystal longsword, 60 intelligence and fast roll OR MLGS medium roll andsome armor for more tankiness. then 24 attunement and you decide about spells but I go :
great farron dart, soul greatsword, and a big hitter of choice (soul spear or greatsoul drge etc) and an extra spell to annoy the hell of others: soul mass is the best but you can also use deep soul etc to force people rolling while you cast something else or recover...
totally different playstyle to the hybrid build though...mostly using spells from afar and dealing with danger when it comes close.
the hybrid aims at closing the gap and meleing while retaining some surprise midrange attacks...
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I used to be an [eclectic gamer] like you, then I took a [dark souls] in the knee.
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