I'm using Fate Core to run a game on a Sword & Sorcery world. We want to use the Weapon and Armor Rules, but I'm not sure how they interact with the Teamwork (FC174) and Mobs(FC216) rules.
One example: A PC has a Fighting skill of 4, and a Weapon of Rating +4. There are 3 Nameless NPCs with Fighting 1, and Armor Ratings of +1. The NPCs has no stress boxes (one shift takes them out the conflict). The NPCs are treated as a single individual using the teamwork rules, so they have Fighting 3 as long as there are 3 NPCs in the conflict. Specifically, the two NPCs are giving a +1 each to the Fighting Skill of one "active" NPC (the one "who rolls the dice"), according to Teamwork rules.
The PC rolls 0, the NPCs also rolls 0. So the PC hits with a +1 shift.
I'm not accounting Weapon or Armor Ratings until the roll is done, since I assume they are only accounted for Damage (as stated in Dresden Files RPG). If a Character fails the attack, then Weapon and Armor Ratings are irrelevant.
First Interpretation: Adding the whole Armor Rating each Time
So the PC has a +1 Shift, and a Weapon Rating +4, for a total of +5 stresses. Since each NPC has Armor Rating +1, the PC spend two stresses on taking one NPC (one for the armor, one for taking him out). That leaves a total of 2 NPcs taken out (4 stresses), and one stress wasted.
If the NPCS would have an Armor Rating of +3 or +4, it would be really hard (and time consuming, with a lot of rounds involved) to take out a group of them.
Also, if the Armor Ratings were added BEFORE individual damage, it would be nearly impossible to take down Mobs with high Armor Ratings. Example: Three NPCs with Armor +3. Same PC and rolls. The PC gets 1+4 shifts. The Mob has a collective Armor Rating of +9, so no damage is done. This interpretation would make the Mobs too hard, and in a lot of instances, virtually unbeatable, so I don't really think of it as a real option.
Second Interpretation: Accounting the Armor Rating just once
Using the Teamwork rules, there is only one "active" NPC , and the rest are just helping him and are supposed to share the consequences (with the Mobs rules changing the way this consequences are shared). So I only accont the "active" NPC's Armor.
In the same example above, the PC has done 5 stresses, and the NPCs has armor 1. So one stress is cancelled by the armor, and then one to take him out. The PC, then has 3 stresses more, enough to take the other 2 bad guys. If the NPCs of the example had Armor 3, then the PC would have taken out just 2 NPCs.
Third Interpretation: Treat Armor Rating as a skill
The Teamwork rule add a +1 for every skill of 1 or better to the Active Character rolling the dices.
In the example above, the total Armor Rating would be 3, so the outcome would be the same as in the first interpretation, but if the Armor Rating was bigger than +1, then the Armor Rating would have less impact in the conflict. Example: Three NPCs, each with an Armor Rating of +3, would have a total "collective" Armor Rating of 3+1+1=5. As in the first Interpretation, I'm assuming the Armor Rating is not being added all together before damage, but instead, the first NPC would need 3+1 shifts to be taken out and the rest 1+1 each one.
So... Is any of this interpretations correct? If not, what is the correct interpretation of the rule?
Subquestion: I've seen that the Dresden Files RPG use the Weapon/Armor Ratings rule and apparently also does a few versions of FATE. Does any of this games also use use the Teamwork and/or Mobs rules for NPCs in combat? Are the Mob rules something new in Fate Core?
Update - Fourth Interpretation: Account the Armor and Weapon each time
In all the above interpretations, I was just assuming that Weapon Rating should be accounted just once. I don't really know why I did that.
So in this interpretation (that right now it's the one making more sense to me), you take in consideration Armor and Weapon Ratings each time. It makes sense, because if multiple opponent attack you, your Armor Rating is there each time for each enemy. In Dresden Files, if you attack multiple enemies (spray attack page 326), your full Weapon Rating is taken into consideration. Extrapolating this to the Mob rules, it makes sense to me that you account Armor and Weapon Ratings for each enemy. Sometimes, just the Weapon Rating would be enough to take them out, and sometimes you will need extra shifts.
I'm pretty sure this is the right answer to this question. What do you think?
PS. Should I answer this question and mark my own answer as the good one? I would rather wait a little in case somebody comes with a better answer...