Necromancer, spell damage
Please tell me, is there any way to raise the damage from bone spells with items other than + skills?
Maybe you can try looking into items increasing your cast rate instead? So with the FCR stat, Faster Cast Rate. It does not increase the damage directly, but it does increase the overall damage output in the end. And I assume that at higher character levels, with appropriate items both on your character and your Mercenary, Mana consumption is no longer really an issue. Hope that helps! 