I was not aware of rage working on ranged weapons. Does it for spells too?

Rage DOES work with ranged weapons, but you must have a melee weapon equipped to use it.
Bows and Crossbows do not qualify so you have to weapon swap back and forth to do it.
Staves absolutely DO qualify as melee wepaons and Rage DOES work with Mage spells.
I found this out the fun way when my Mage bought up Man-At-Arms 5 for the Magic Resistance.
Rage + Pyromancy generates some outrageous damage.
