I've been DM'ing for a while, but have a newbie question that has always plagued me...

For the creature Yochlol to use as an example, the resistance description reads, "Damage Resistances cold, fire, lightning, bludgeoning, piercing, and slashing from nonmagical weapons."

Does this mean it has resistance to cold, fire, and lightening (ie spells) AND THEN bludgeoning, piercing, and slashing from non magical weapons? Or is it cold, fire, and lightening from weapons that are not magical (which does not make sense to me). 

Any help is appreciated! 

It's the first option, resistance from

• Cold
• Fire
• Lightning
• Bludgeonning, piercing and slashing from non-magical weapons

Thank you so much!!!

 There is a bit of a punctuation error in your quoting: the Line actually reads "Cold, Fire, Lightning; bludgeoning, piercing, and slashing from nonmagical weapons.  The semicolon is important.

So you read the Bludgeoning, piercing, and slashing as the only things applies to the nonmagical weapons.  Were as cold, fire, and lighting the source does not matter

The real question is which non magical weapons do damage that is not bludgeoning or piercing or slashing.

None, all base weapons do one of those three.

You can make an attack with a torch and that does 1 point of fire damage, but it's not a weapon.

If you look through the equipment section of the phb, you'll see all the weapons do bludgeonning, piercing or slashing damage

From the Monster Manual: 

Vulnerabilities, Resistances, and Immunities

Some creatures have vulnerability, resistance, or immunity to certain types of damage. Particular creatures are even resistant or immune to damage from non-magical attacks (a magical attack is an attack delivered by a spell, a magic item, or another magical source). In addition, some creatures are immune to certain conditions.

I have seen many monsters with resistance or immunity to physical non-magical attacks but, not a whole lot that defines magical elemental damage from non-magical elemental damage.

Quote from Davedamon >>

None, all base weapons do one of those three.

You can make an attack with a torch and that does 1 point of fire damage, but it's not a weapon.

If you look through the equipment section of the phb, you'll see all the weapons do bludgeonning, piercing or slashing damage

 Apparently, but why in the monster manual do they always specify all three

"bludgeoning, piercing, and slashing damage from nonmagical weapons"

when they could just say

"damage from nonmagical weapons"

Quote from GregCa >>

Quote from Davedamon >>

None, all base weapons do one of those three.

You can make an attack with a torch and that does 1 point of fire damage, but it's not a weapon.

If you look through the equipment section of the phb, you'll see all the weapons do bludgeonning, piercing or slashing damage

 Apparently, but why in the monster manual do they always specify all three

"bludgeoning, piercing, and slashing damage from nonmagical weapons"

when they could just say

"damage from nonmagical weapons"

 

 From a design perspective, the way of writing this, is not bad, because it is possible to have only one or two of these resistances and not only all three. Also, specifying the actual damage types helps with sorting out what damage sources might fall into these categories.

Alchemist's Fire or an arrow that you've lit on fire is a nonmagical weapon. This way you don't have arguments popping up about whether or not they have resistance to that. I'd rather have a clear, specific rule that prevents that kind of debate.

Quote from pocketmouse >>

Alchemist's Fire or an arrow that you've lit on fire is a nonmagical weapon. This way you don't have arguments popping up about whether or not they have resistance to that. I'd rather have a clear, specific rule that prevents that kind of debate.

 I wouldn't agree with that, if you light an arrow on fire the "arrow damage 1-6 piercing" is not going to suddenly count.

Fire damage is fire damage, its not weapon damage.  

Quote from Voras >>

Quote from GregCa >>

 

Also, specifying the actual damage types helps with sorting out what damage sources might fall into these categories.

 I suppose, I prefer brevity but if you are looking at your first ever monster with those immunities I guess it makes sense.

Yeah, so a semicolon is stop punctation... this video explains it really well. Anyway as to your original question, obviously it's the one that makes sense.