Shattered Kingdoms

I was wondering if MR stacks with the other things you can get while enchanting such as willpower/fort/ref.

What is the relationship, if any, between them? If I have 4 mr and 4 willpower will that give me + 8 to will saves?

No, they will not stack like this.

As I understand, magic resistance gives the character a chance to resist the effects of the spell entirely- the magic either affects you or it does not. Magic Resistance applies to ALL spells- whether it be a "heal" spell, a "mirror image" spell, or a "fireball" spell.

Saving throws affect only 'attack' spells (not spells like healing, etc). Once your Magic Resistance has been checked, if you don't resist the spell completely, then you get your saving throw. If you save against the spell, you take only partial damage. If you don't save against the spell, the spell does full damage.

Hope that helps.

That is how I understood it, but I think that there are some spells that you can save with fort/will/reflex and also take no damage (instead of partial damage).

Taking no damage is more the province of magical protection. Besides its effect on armor, it reduces the damage taken by hostile spells - potentially to zero, which gives a special message. Of course, making a successful reflex save against a damage spell certainly makes it easier to get a no-damage result.

MP is better than reflex, stack willpower and fortitude.