Immunity, Resistance, and Vulnerability from XGTE

[BeyondLimitatio]

On page 5 of Xanathar's Guide to Everything, there is a clarification on how Resistance, Vulnerability, and Immunity are applied on damage. However, this brought up a couple of questions that I would like clarified a little. First though, here is what it says (paraphrasing here):

The order you apply effects onto damage is: 1) Any relevant damage immunity, 2) Any addition or subtraction to damage, 3) One relevant damage resistance, 4) One relevant damage vulnerability

Ok, so with that said, here are my questions:
1) When it says "addition or subtraction" to damage, what is considered a part of that? Like for example, if I attacked someone with immunity to slashing with a longsword, obviously my damage is negated, but what about my strength bonus? What if I crit on that attack, does the extra damage dice get negated?
2) Since I mentioned the strength bonus, what type of damage type is that considered? More of whatever the original attack was, untyped, or something else? So imagine if I did a longsword attack onto an enemy, dealing 1d8+4 (str mod) damage. Let's assume I rolled max, so 12 total. Against someone with slashing resistance, would that be 6 damage (half of 12), or 8 damage (half of 8 plus the 4 from STR)?
3) Let's say that I attack with a Flame Tongue longsword against an enemy who has a resistance to slashing as well as a resistance to fire damage. So it deals 1d8 slashing plus 2d6 fire damage on a hit. The rule says "one relevant damage resistance", so would I only get to pick one of either slashing OR the fire to halve? Or do both apply to their respective damage? The wording is a little unclear here.

[MeeposFire]

On page 5 of Xanathar's Guide to Everything, there is a clarification on how Resistance, Vulnerability, and Immunity are applied on damage. However, this brought up a couple of questions that I would like clarified a little. First though, here is what it says (paraphrasing here):

The order you apply effects onto damage is: 1) Any relevant damage immunity, 2) Any addition or subtraction to damage, 3) One relevant damage resistance, 4) One relevant damage vulnerability

Ok, so with that said, here are my questions:
1) When it says "addition or subtraction" to damage, what is considered a part of that? Like for example, if I attacked someone with immunity to slashing with a longsword, obviously my damage is negated, but what about my strength bonus? What if I crit on that attack, does the extra damage dice get negated?
2) Since I mentioned the strength bonus, what type of damage type is that considered? More of whatever the original attack was, untyped, or something else? So imagine if I did a longsword attack onto an enemy, dealing 1d8+4 (str mod) damage. Let's assume I rolled max, so 12 total. Against someone with slashing resistance, would that be 6 damage (half of 12), or 8 damage (half of 8 plus the 4 from STR)?
3) Let's say that I attack with a Flame Tongue longsword against an enemy who has a resistance to slashing as well as a resistance to fire damage. So it deals 1d8 slashing plus 2d6 fire damage on a hit. The rule says "one relevant damage resistance", so would I only get to pick one of either slashing OR the fire to halve? Or do both apply to their respective damage? The wording is a little unclear here.

1) In most cases the attribute bonus to damage is of the same type as the weapon attack you are making so for your sword attack your str bonus would increase the slashing damage so it would be immune to that. The most common and easy find example of this idea is the heavy armor master feat where you subtract 3 points of damage to non-magical slashing piercing and bludgeoning damage. In that case you subtract that number from the damage before you apply resistance. Most (if not all) things that give a bonus of any sort of damage that is not the same as the original attack/damage effect will specify a damage type in which case for purposes of resistance means they are two different damage effects.

2. For that weapon attack it would be the same damage type as the weapon delivering it. Remember that weapon damage in general is weapon dice+ attribute unless otherwise stated. However do notice that while this is true for basic weapon damage not every instance of attribute bonus to damage is basic weapon damage. For instance pact of the blade warlocks can take an invocation that gives +cha mod in necrotic damage to their pact weapon attacks. IN that case the weapon would deal its damage dice+attribute bonus (all the same damage type) and then +cha bonus necrotic damage.

3. Each damage type can only have one resistance applied to it. The slashing damage and fire damage are separate and each can have one resistance applied to it. What the one resistance rule is trying to avoid is having tow apply to one damage type instance for example if you hit with a normal longsword on an enemy that is resistant to normal weapon attacks and has a separate resistance to slashing attacks in general. In that case you would only apply resistance once even though the resistance could potentially work twice but the rule says you only apply one. If you used a magical longsword the target would stil get its resistance since while the normal weapon resistance would now be ignored the general slashing resistance would still apply. If you attacked with a magic war hammer then no resistance would apply. If you attacked the enemy with a magical flaming longsword the slashing damage would be resisted but the fire damage would not.

[BeyondLimitatio]

Perfect, you pretty much said exactly what I was thinking and had played as in the past. The wording was a little awkward in XGTE though, so figured it was better to double check.

[Talamare]

This wording was already in the PHB pg197