Redbeak

What does it increase?

Physical damage
Spell damage
Elemental damage (spell damage =?= elemental damage)
projectile damage

If it adds 100% to all then Ethereal Knive should becomes:
(2+physical increase)(2+spell damage)(2+projectile damage)

Or does it work on a different way?

Edit:
What about burning damage?

Edit2:
Or is it 100% MORE dmg?

bump because i also would like to know

bump!

bump

INREASED damage, any kind they might be, aren't multiplicative, they are additive. The only exception would be skill that converts some physical damage to elemental damage, where the increased physical damage and increased elemental damage wouldn't be added one to the other. I do not know how Redbeak would work in this scenario, but in all the other, it does 100% increase of the damage and only does it once. EX : (Your base damage) * ( 1 + physical damage increase + spell damage increase + redbeak damage increase) = final damage