In Bloodborne you can buff your weapons with damage scaling, either physical, or elemental. Physical bases damage off three stats: Strength, Dexterity, or Arcane.

When looking at the effects of the Arcane Gems, the wiki states:

If used in in conjunction with a gem that gives bolt or fire damage, the Arcane Blood Gemstone will overwrite the previous gem's effect and replace all damage with Arcane.

So if I have one gem that deals 16% Bolt damage, then I apply a gem that boosts my Arcane Scaling by 15%, does that mean my Arcane scaling goes up by 31% in total?

1 Answer

No, the Arcane damage will cancel the bolt damage and do only arcane damage if you use only flat values gems (ex: +30 Arcane) that adds a flat amount of damage in your weapon as you can see here.

But if you put a %elemental gem on a physical weapon the physical damage will be 0 and the weapon will do elemental damage scaling on your arcane values.

the Arcane Scaling gem you have will not boost your bolt damage by 15% but will increase of the 15% the scaling of arcane, so no you won't have +31% fire damage but will increase your damage for the Arcane values of your build.

Now if you want to do a Bolt build i suggest using a good %bolt gem (+23%) and 2 scaling arcane gems like yours, in order to increase the scaling based on your arcane.

Visit this site for good advices for Arcane/fire/bolt builds. And this for a good Arcane guide

Sorry for the unclarity

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