Question about flame wall add damage to projectile

I have a question about flame wall add damage to projectile.

Does the damage is added to the base damage or the final damage ?


Meaning for exemple, my projectile deals 100 base damage, I have 100% inscreased damage and the flame wall add 100 damage.

When passing through, the projectile will deal 300 or 400 damage ?

Flame wall adds x to x flat damage to projectiles that pass through.
this is base damage, meaning if it adds 10 flat, you will have 10 + 100% increase fire damage on top of your projectiles normal damage