24
\$\begingroup\$

The Resilient feat (PHB, p. 168) allows you to increase one ability score by 1 and gain proficiency in saving throws using the corresponding ability. In essence, taking the Resilient feat and picking Constitution adds a flat bonus to all Constitution saving throws, increasing from +2 to +6 as you gain levels.

The War Caster feat (PHB, p. 170), among other benefits, grants advantage on Constitution saving throws that you make to maintain your concentration on a spell when you take damage.

It seems like War Caster would improve the consistency of passing most Concentration checks, but that Resilient (Con) would improve the chances of passing when taking larger amounts of damage that result in a higher DC check.

Which of these two feats statistically provides a greater benefit in helping a character maintain concentration on a spell?

\$\endgroup\$
  • 4
    \$\begingroup\$ related question is here ... \$\endgroup\$ – KorvinStarmast Aug 29 '18 at 18:23
  • 1
    \$\begingroup\$ @NautArch Standard Proficiency. I limited the question to Concentration so the question wouldn't be too broad, but other considerations would be interesting too. \$\endgroup\$ – mgillesp Aug 29 '18 at 18:41
  • \$\begingroup\$ I've tried to clarify the wording a bit. \$\endgroup\$ – V2Blast Aug 29 '18 at 18:50
  • 6
    \$\begingroup\$ @Nathan Please don't add answers, partial or full, to the comments of a question. You could create your own answer or comment on someone else's, but the question's comments should be reserved for getting clarification or providing relevant information for research. \$\endgroup\$ – Daniel Zastoupil Aug 29 '18 at 19:01
24
\$\begingroup\$

The proficiency bonus determines which feat is superior.

I made a "success chance vs DC" graph to compare Resilient and War Caster.
Success Chance vs DC

How to read the graph.

War Caster is blue, while Resilient is red. By default1 the solid lines have 2 CON as that is a reasonable modifier for casters. The blue dotted line has 1 less CON.

• If your character has an even constitution score before choosing the feat, then compare the solid blue line with the red lines;
• else if your character has an odd constitution score before choosing the feat, then compare the dotted blue line with red lines.

While analyzing the graph, keep in mind that the DC is typically 10 to 15 during low to mid levels, while even at high levels the DC rarely exceeds 25, although this can vary significantly from group to group.

Resilient vs War Caster comparison.

For the purpose of concentration checks, Resilient is strictly better than War Caster when your proficiency bonus is:
• equal or greater than +4, if your constitution is odd prior to choosing the feat;
• equal or greater than +5, if your constitution is even prior to choosing the feat.

War Caster offers the most benefit (equivalent to a +5 bonus) when the DC is 11+CON, and no benefit when the DC is greater than 20+CON. Therefore, should you suffer massive damage (around 40+2*CON) and remain conscious, War Caster will offer little to no benefit, whereas Resilient will offer some benefit even if you proficiency bonus is small. How often you receive massive damage varies from group to group.

A +9 bonus to constitution saves guarantees passing the minimum DC of 10. Resilient goes a long way towards achieving that +9 bonus, whereas War Caster does not.


  1. The graph is somewhat interactive: it has a slider called mod with which you can easily change the constitution modifier.
\$\endgroup\$
  • 3
    \$\begingroup\$ That graph is excellent. It does a great job showing where each feat shines. \$\endgroup\$ – mgillesp Aug 29 '18 at 22:20
  • 2
    \$\begingroup\$ This is a neat toy! Is it possible to add labels to each of your lines? I was able to infer the intent of each of the red lines syncing with the the periodic bumps in proficiency, but I think it'll be improved if that's spelled out a bit more clearly. \$\endgroup\$ – Pyrotechnical Aug 30 '18 at 17:00
  • 1
    \$\begingroup\$ @Pyrotechnical I added some labels and you are right, the graph is way more legible now. Though the labels overlap slightly, and the red labels become inaccurate when I increase the slider too much. \$\endgroup\$ – Ruse Aug 30 '18 at 18:09
  • \$\begingroup\$ As I read your graph, if I don't expect my character (cleric) to get past 12th level (I don't think the campaign will last that long) then War Caster looks pretty good. (Con of 16 currently). \$\endgroup\$ – KorvinStarmast Sep 6 '18 at 13:24
5
\$\begingroup\$

It depends on your level (among other things)

tl;dr: Advantage roughly equals a bonus of +5.

Hence, until you're level 13 and your proficiency bonus increases to +5, War Caster will be more useful. If the ability score increase also raises your CON modifier, you reach the tipping point 4 levels earlier, at level 9.


Let's do a little more math. Assuming you often take less than 20 damage, you will usually have to beat DCs of 10. Assuming you have 14 CON, let's take a look at some anydice.com calculations:

Probability to roll at least 10 with advantage and a +2 modifier: 87.75%

Probability to roll at least 10 without advantage and a +5 modifier (+3 prof): 80%
Probability to roll at least 10 without advantage and a +6 modifier (+4 prof): 85%
Probability to roll at least 10 without advantage and a +7 modifier (+5 prof): 90%
Probability to roll at least 10 without advantage and a +8 modifier (+6 prof): 95%

Clearly, your best option would be getting a +9 modifier, in which case you simply couldn't fail concentration checks with a DC of less than 10.
However, that would require 16 CON and the maximum possible proficiency bonus, so it's unlikely you'll get there before you'll have to suceed on higher DCs than 10.

Anyways, with 14 CON (although that shouldn't matter too much), you need at least a proficiency bonus of +5 to get better results than by choosing War Caster. If your CON score is uneven before you take the feat, it will also increase your CON modifier by one, meaning you only need a +4 proficiency bonus (which is reached at level 9).


Be sure to keep in mind that War Caster provides other benefits - being able to cast (certain) spells as opportunity attacks can be really useful. For this reason, I'd always advise choosing War Caster.
Then again, Resilient benefits all CON saving throws, not just concentration saving throws, so I guess it depends on what you want.

However, if you can spare the ASIs (e.g. because you're a variant human and get one free feat anyways), choosing both can be really powerful.

Probabilities when choosing both feats:

Assuming you spend your first two ASIs at level 4 and 8 on actual ability score increases for your main stat and are playing a variant human, you'll be level 12 by the time you accumulate 2 feats.

This means a proficiency bonus of +4. Assuming you have 14 CON and don't gain a modifier increase from Resilient, you have a 90% chance to roll 13 and higher, and a 50% chance to roll 21 or higher.

Anydice link; select the "at least" view.

\$\endgroup\$
5
\$\begingroup\$

At all levels of play, the answer depends on how much damage is being dealt in a single blow. But there are general rules that can be followed:

  • Warcaster is better when the damage is near an extreme, i.e. really high or really low.
  • The Higher Level that the caster is, the better Resilient is.
  • These two feats don't conflict with each other, so if you have the option of getting both, you should get both.

Let's take a few case studies.

Level 1 Wizard, 14CON, taking 4 damage

In this scenario, they would naturally have a +2 to their Constitution Saving Throw. Since 4 damage is below the Concentration Check minimum of 10, the check is set to 10. As a result,

  • Normally, they have a 65% chance to succeed on the roll (8 or better)
  • With Resilient, they have a 75% chance to succeed (6 or better)
  • With Warcaster, they have a 88.75% chance to succeed (8 or better on at least one roll)

So we see quite clearly that in this scenario, Warcaster is better. You go from failing 1/4 of your rolls with Resilient to failing < 1/8 of your rolls with Warcaster.

Level 7 Wizard, 14CON, taking 30 damage

That's a lot of damage, but pretty plausible for getting hit by a nuke spell. The DC for the concentration check is now 15, so...

  • Normally, they have a 40% chance to succeed (13 or better)
  • With Resilient, they still have a 55% chance to succeed (10 or better)
  • With Warcaster, they have a 64% chance to succeed (13 or better on at least one roll)

Once again, Warcaster is better, though the difference is less pronounced: Warcaster is only about 20% better than Resilient.

Level 16 Wizard, 18CON, taking 22 damage

Things have changed a bit. They're way stronger, but they're still getting hit by a pretty mild attack (for their level). DC is 11, here's how the stats shake out:

  • Normally, they have a 70% chance to succeed (7 or better)
  • With Resilient, they have a 95% chance to succeed (only fails on a NAT1)
  • With Warcaster, they have a 91% chance to succeed (7 or better on at least one roll)

The odds have flipped in Resilient's favor, and by a significant margin: Resilient causes you to fail about half as frequently as Warcaster does.

Level 19 Wizard, 20CON, taking 34 damage

This is a pretty decent for this level. DC is 17, here's the stats:

  • Normally, they have a 45% chance of success (12 or higher)
  • Resilient gives a 75% chance of success (6 or higher)
  • Warcaster gives a 69.75% chance of success (12 or higher on at least one roll)

Resilient once again wins out, though they're both very close to each other in this situation. The raw percentage point difference is greater than in the previous example, but Resilient is only about 20% better than Warcaster in terms of overall failure prevention.

\$\endgroup\$
  • \$\begingroup\$ The DC is only half of the damage taken. \$\endgroup\$ – mgillesp Aug 29 '18 at 21:13
  • \$\begingroup\$ The rule for Concentration checks is that the DC is 10 or HALF the damage taken, whichever is greater, so your examples with damage in excess of 20 need amending. \$\endgroup\$ – cpcodes Aug 29 '18 at 21:13
  • \$\begingroup\$ Ah, crap. I'll fix that. Give me a few minutes... \$\endgroup\$ – Xirema Aug 29 '18 at 21:14
  • 3
    \$\begingroup\$ "Warcaster is better when the damage is near an extreme, i.e. really high or really low." I have to disagree, Resilient increases the highest DC you can save against. \$\endgroup\$ – Ruse Aug 30 '18 at 0:10
  • 3
    \$\begingroup\$ @Ruse: And beyond that, advantage gives its biggest benefit when the natural roll required is an 11, with decreasing advantages as you move towards the extremes. When you need a natural 11, it's equivalent to a +5 bonus (you go from 50% success rate to 75%). If you need a natural 2 or a natural 20, it's ever-so-slightly worse than a +1 bonus. The minimum DC of the concentration check means you're less likely to be at the really low extreme in early levels (you'll always need a lot more than a natural 2 to pass), but in general, Warcaster is least useful when the damage is near an extreme. \$\endgroup\$ – ShadowRanger Aug 30 '18 at 5:25
3
\$\begingroup\$

War Caster is better at the beginning, worse later

I calculated with 12 Con for War Caster, and 14 for Resilient(Con), this being an optimization question.
Once against 10 damage, this being the most common even on higher levels, once against 10 + 2 * Level (I find this a good approximation). On the Y-axis is the chance to succeed, X-axis is level.

Damage 10: dmg 10

Damage 10 + 2 * Level: enter image description here

It is visible that in both cases Resilient pulls ahead around level 9-10.

You should take Resilient anyway

Forget about concentration for a minute.

Constitution is one of the top two saves. It is common, and the effects are nasty. Both Wisdom and Dexterity are even more common, but Dexterity usually just saves you some HP, and all the others are very rare. If you are not proficient with Wisdom saves, it is a good idea to take Resilient(Wis). Resilient(Con) is almost as useful in this regard.
So helping Concentration is just a side benefit, what you get besides is worth a feat alone. And there is the half HP per level from the +1 Con.

Would you take War Caster if it did not provide a bonus to concentration checks?

Exception

If you can reliably provoke opportunity attacks, have a good cantrip available, have a decent Con save anyway, only than should you pick War Caster over Resilient(Con).
The single intersection of these requirements I have ever seen was a Paladin/Warlock with Polearm Master1.


1) Paladin with Aura of Protection for the acceptable Con save, Warlock for the cantrip (could be Sorcerer) and Polearm Master for reliable2 opportunity attacks
2) Most DMs rarely provoke opportunity attacks with movement, and spells that force an opportunity attack (Dissonant Whispers for example) are costly, and can be saved against

\$\endgroup\$
  • \$\begingroup\$ My cleric has a 16 Con. If I take war caster, I am good to about level 12 ... and I don't think the campaign will last beyond that, if it gets that far. I like your illustration. \$\endgroup\$ – KorvinStarmast Sep 6 '18 at 13:37
  • \$\begingroup\$ @KorvinStarmast "You should take Resilient anyway", Con saves are more frequent than OAs. Clerics can cast while holding a shield, and no-one should dual wield. \$\endgroup\$ – András Sep 6 '18 at 14:39
  • \$\begingroup\$ yes, I am very tempted. Good points all around. \$\endgroup\$ – KorvinStarmast Sep 6 '18 at 14:40
  • \$\begingroup\$ @KorvinStarmast, what I can't understand why are people drawn at all to Warcaster (and Charger, and dual wielding) \$\endgroup\$ – András Sep 6 '18 at 15:25
  • 1
    \$\begingroup\$ in my case it was due to my first cleric being a front line fighter as well as a caster. The DMs were a little sticky about components, etc ... the other reason is I prefer rolling with advantage since two rolls gives me a better chance to overcome that one lousy result (a three, arrgh) ... \$\endgroup\$ – KorvinStarmast Sep 6 '18 at 15:36
-3
\$\begingroup\$

Resilient (CON) is always better than War Caster

When you have Resilient (CON) it is applicable in all CON ST
When you have War Caster it apply only on concentration when taking combat damage - no advantage if you receive fall damage

What about all other conditions saves where you do not have any benefit from War Caster but have from Resilient (CON).
Also it is extremely beneficial if you have odd number in constitution - because than you will receive extra 1HP with every level later on and that is extremely important for wizards who have low hit points

\$\endgroup\$
  • 3
    \$\begingroup\$ Hello and welcome! Mgillesp didn't ask which feat is best overall, they asked which feat improves the chances of maintaining concentration. Moreover, "War Caster it apply only on concentration when taking combat damage - no advantage if you receive fall damage" is factually wrong. \$\endgroup\$ – Ruse Feb 28 at 21:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.