D&D General Reducing incoming damage: +1 =/= +5%

[Charlaquin]

I recall that in the early days of World of Warcraft, the concept of "effective health" for tanks was floating around. Basically, the idea was that if you had 1,000 health and 50% damage reduction, your effective health was 2,000 (1,000/50%).

Using the same metric but with the more stochastic way armor works in D&D, we can see that a 12th level fighter with Con 14 will have 100 hp (assuming fixed hp). Looking over the first page of results when searching D&D Beyond for CR 12 creatures (yes, I know 5e is unlike 3e and Pathfinder in that it doesn't assume fights against roughly "on-par" creatures, but it's helpful to get a baseline) shows that most have an attack bonus of +7 to +9 with occasional outliers, so I'm going to simplify to +8. If the fighter has full plate, that's an AC of 18, meaning the monsters hit on 10+ and miss on 9-, which means the fighter only takes 55% of incoming damage. So the fighter has an effective health of 100/0.55 = 182 hp.

Adding a +2 AC bonus (e.g. a shield) to the fighter lowers that to 45%, so they now have 222 effective hp, a 22% increase. Adding a second +2 bonus (e.g. shield of faith) lowers it even more to 35%, for 286 effective hp, which is a 57% increase over the baseline or a 29% increase over a single +2 bonus.

This is of course a simplification. For one thing, I've ignored crits, because the extra damage from one varies in 5e. I've also ignored damage that bypass AC, which is fairly common. But it shows a tendency that boosting AC has accelerating returns (or whatever the opposite of diminishing returns is).

Though that’s more useful in WoW where you have aggro-management mechanics, whereas in 5e, abilities that punish opponents for targeting other party members is few and far between.

 

[FrogReaver]

I like GWF at least when coupled with greatswords.

I run long adventuring days, and your experience does not chime at all with mine. It likely comes down to nuances in what campaigns focus on and overall context at the table. What are other party members doing? What are they facing? For the last couple of years for us that has been OOTA and then ToA. Fighters (typically battle masters), warlocks, paladins, bards and clerics have featured highly.

However, be wary of thinking of it as +1 AC in isolation: I certainly wouldn't advocate that. Defense is much less valuable on characters with low AC, who might well benefit more from other tactics.

Imo it’s the exact opposite. I’d rather have +1 ac on a lower ac character than a higher ac one from a party combat efficiency standpoint.

mainly because there’s not great ways to force enemies to attack the higher ac character (dm fiat but that’s target dm dependent)

 

[clearstream]

I like GWF at least when coupled with greatswords.

GWF feels like a wasted choice, to me. That's mechanically. It is flavourful.

Imo it’s the exact opposite. I’d rather have +1 ac on a lower ac character than a higher ac one from a party combat efficiency standpoint.

Terrible choice, but okay

mainly because there’s not great ways to force enemies to attack the higher ac character (dm fiat but that’s target dm dependent)

Agreed one needs a plan for that. Trip. Fear effects. Sentinel. Hard to ignore damage. Inconvenient spells that you are concentrating on (if a martial that casts).

 

[clearstream]

Though that’s more useful in WoW where you have aggro-management mechanics, whereas in 5e, abilities that punish opponents for targeting other party members is few and far between.

It takes a group effort, is what I am finding. A tank working in tactical isolation can struggle to achieve much.

 

[Charlaquin]

GWF feels like a wasted choice, to me. That's mechanically. It is flavourful.

It’d be quite good if it actually gave Brutal 2 instead of the toned-down version it currently gives.

 

[FrogReaver]

GWF feels like a wasted choice, to me. That's mechanically. It is flavourful.

Since this thread isn't about GWF and I agree that defense is a tad better when using a greatsword I'm going to drop this tangent.

Terrible choice, but okay

Why? Can you guarantee the lower AC character doesn't get focused on more than the higher AC character?

Agreed one needs a plan for that. Trip. Fear effects. Sentinel. Hard to ignore damage. Inconvenient spells that you are concentrating on (if a martial that casts).

Sure, if you use certain abilities you can have enemies attack you more often. All of those abilities are investments, most have a chance of failing, most only effect a single enemy while also only lasting a single round even when they do work. While they can cause you to be attacked a bit more, i'm not seeing how they cause you to be attacked substantially more? Maybe you can elaborate on your planned method for that?

 

[FrogReaver]

It takes a group effort, is what I am finding. A tank working in tactical isolation can struggle to achieve much.

IMO. When other players are actively required to do something for your sole reason for existing to matter, there's something wrong.

I once built a Bear Totem Barbarian 4 Swashbuckler Rogue X in a no feat game and had him be the tank. I even maxed out my con with my ASI's instead of increasing my 14 str/14 dex. He was the only melee character in our party. Worked great as a tank and didn't need party help to achieve that goal. I could engage enemies far enough away that they often couldn't move from me and attack my allies - and I had enough speed due to cunning action that they couldn't just run past me and make me not be able to attack them next turn - and in the event they did try to dash away from me that took alot of damage from sneak attack. When desired I could even grapple anything large or smaller with no issues due to expertise and advantage with rage.

The point is I'm not stranger to creating effective tanks - but there's alot more to them than high effective hp.

 

[Mordhau]

Tanking in 5e I find somewhat works, but you have the issue of only having one reaction.

You can do a lot with Shieldmaster though, which tends to be underrated. Being able to shove as a bonus action is very useful for setting up choke points. Being able to knock prone is useful to and it halves movement which may make it impossible for them to attack anyone but you (of course this is where you need party cooperation. If your goal is to lock someone in place, so they can only attack you it's not much help if the rest of the party then rush in to attack them because they have Advantage.

 

[Krachek]

Defensive combat style is great for those who don’t attack every round,
or switch weapon type,
or simply want a static bonus that don’t need management.

 

[Mordhau]

GWF is fairly bad. I think the main comparators are archery, defense, dueling and perhaps now interception. Blindfighting is probably too conditional.

It is - that's what I meant. If you want to use a Great-weapon I think Defence style is the better choice.