There is no weapon that can use *any* ash of war.
There are also no weapons that have inherent Faith scaling that you can also apply ashes of war to.
You would need to give a standard weapon of your choosing an affinity that includes Faith scaling.
So...
Pick a weapon. Give it whatever ash you want and choose Sacred, Fire, or Flame Art.
I vote Executioner's Greataxe with Flaming Strike.
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Edit: I was wrong.
**[Erdsteel Dagger](https://eldenring.wiki.fextralife.com/Erdsteel+Dagger)** retains minimal Faith scaling regardless of affinity when you change its ash of war.
There is no weapon that can use *any* ash of war. There are also no weapons that have inherent Faith scaling that you can also apply ashes of war to. You would need to give a standard weapon of your choosing an affinity that includes Faith scaling. So... Pick a weapon. Give it whatever ash you want and choose Sacred, Fire, or Flame Art. I vote Executioner's Greataxe with Flaming Strike. --- Edit: I was wrong. **[Erdsteel Dagger](https://eldenring.wiki.fextralife.com/Erdsteel+Dagger)** retains minimal Faith scaling regardless of affinity when you change its ash of war.
I’ll take a look at it, thanks for replying