Survivability with multiple Warding Bonds

Question

This question is a follow up of This Question concerning casting Warding Bond on multiple allies. It was found that This Tweet confirmed my suspicions that it is possible, given a separate pair of rings for each separate creature I want to effect when I cast Warding Bond, to share damage with multiple allies.

Now that we know this is possible, I am curious as to the nature of the survivability of my level 5 Hill Dwarf War Cleric using the Tough feat and taking the average HP every level up for a current total of 53 HP.

My party consists currently of myself (War Cleric), a Life Cleric (also a Hill Dwarf), a Rogue, 2 weapon Fighter, and a Warlock. Next session we will be joined by a Wizard. We are at a static level 5.

The rogue is wearing the matching ring of my first pair of Platinum Rings that are required to cast the spell.

It is safe to assume the more simultaneous bonds I have active at any given moment, the lower my survival rate becomes. Sharing 1/2 damage from multiple sources is bound to be hazardous since there is no way to reduce that damage even farther.

How thin can I spread myself without being suicidal?

Answer 1

Warding Bond ends if it is cast on either creature a second time.

All of this would be math is pointless.

Read. Your. Spells. People.

Warding bond says:

The spell ends if you drop to 0 hit points or if you and the target become separated by more than 60 feet. It also ends if the spell is cast again on either of the connected creatures.

If you have cast Warding Bond and someone cast Warding Bond on either you or the target of your casting, then the casting of Warding Bond by you is ended.

Answer 2

I will attempt to clarify the potential value of this by using average combat mechanics, and then see where the multiple warding bonds will provide value.

Overall, your party and the enemy will do average damage of:

(Probability of Hit) x (Average Damage) x (number of rounds)

Note that the Probability of Hit is related to (target AC - Attack Bonus), and is 50% when (target AC - Attack Bonus) = 10.5

The winner of an attrition based conflict (see Lanchester Model of Attrition Warfare) will be the side that can inflict average damage until the enemy is dead, and then have some residual strength of their own. In D&D parlance, that means that:

(Allies HP) / (Enemy Rate of Damage) > (Enemies HP) / (Allies Rate of Damage)

From this, your Warding Bond will not affect your Allies Rate of Damage, or your Enemies HP, so you are working entirely on the left hand side of the inequality. In order to be successful, your dwarf must survive enough damage to provide your allies resistance so that you get a two fold bonus to the inequality (since Enemy Rate of Damage is reduced by 1/2).

In addition, the AC bonus that you provide to those affected with the spell gives them an additional 5% reduction in the enemies probability of damaging them per round. This will further serve to reduce the damage taken on the left hand side of the equation.

The answer to your question lies in comparing all of the parameters that I have listed. I will facilitate this by providing four bounding conditions:

1. The enemy has vastly more HP than your dwarf, relative to the average rate of damage, and they do damage at a higher rate than your allies. This is the suicidal case you reference.

2. The enemy has far more HP than your dwarf, but they do damage at a much lower rate.

3. The enemy has far fewer HP than your dwarf, but they do damage at a much higher rate.

4. The enemy has far fewer HP than your dwarf and they do damage at a much lower rate.

In case 1, it is unlikely (5%) that you will see the benefit of the spell, and your dwarf is very much at risk. In case 4, it is also unlikely that you will see the benefit of the spell, largely because your allied force didn't need it.

In cases 2 and 3, the benefit of the spell can swing the tide. There isn't a clear cut use case, since it will depend on the specific engagement. In these cases, if the enemies average damage is more than double your force's average damage, then the spell is a bad idea (so is combat).

In this case, we now switch back to the first formula.

(number of rounds for attrition) = (Enemy HP) / (Probability of Hit * Average Damage)

using a Ph of 50%, the dwarf will survive (most of the time) when:

(Enemy HP) / (0.5 * Friendly Avg Damage) < (Dwarf HP) / (0.45 * 0.5 * Enemy Avg Damage)

(Note that the 0.45 is for the AC change, and the 0.5 is the resistance).

This tells us that the probability is that the dwarf will survive ~50% of the time when you have ~1/2 as many hit points as the opposing force. If you have more HP than that, you will survive more. If you roll better (or the enemy rolls worse) you will survive more.

From this, you could consider spreading yourself "that" thin. Pick the hardest hitting allies who are the weakest, and start bonding them until you get to a number (understanding that the enemies rate of damage to the dwarf will go up linearly with each ally you bond) that is close to the ratio of your HP to the entire enemy force's HP.

ASSUMPTIONS:

1. The dwarf is not fighting. If the dwarf is ALSO taking direct damage, it complicates the equations a bit (makes them second order), and I would need a lot more detail to solve them (including the specific parameters of the engagement on both sides).

2. There are no area based spells being cast against the multiple bonded allies

3. No consideration was taken for the enhancement in saving throws for bonded allies (requires much more specific model).

Answer 3

You can survive this

You can increase survivability drastically through this loophole. However, it requires everyone else to be level 2 clerics (or, at the very least, have some magic items).

Key Note: If you are cast warding bond upon, you may still cast warding bond yourself without ending the spell. This is because you are not the target of your own spell. This allows you to build a chain of characters linked by this spell.

---

The steps:

1. Cast warding bond onto a second cleric (cleric \$2\$). This counts as the spell being cast on that cleric only.
2. Have cleric \$2\$ cast the same spell on a third cleric (cleric \$3\$). Since this spell targets someone other than the caster, then the spell does not break. You now have a chain of 3 clerics.
3. Repeat until cleric \$N\$, where \$N\$ is the total number of clerics in the party.

The damage calculation:

1. If cleric \$N\$ takes \$M\$ damage, then that damage is split in half due to resistance, so \$M/2\$.
2. Cleric \$N-1\$ takes \$M/2\$ damage. However, since warding bond is also active on this one, they have resistance to that damage. So, they take \$M/4\$.
3. Cleric \$N-2\$ takes \$M/8\$ damage for the same logic as step 2.
4. In general, Cleric \$N-a\$ will take damage equal to $$M\over 2^{a+1}$$

The effect of this, overall, is that someone taking 100 points of damage will be able to split that 100 HP to everyone in the party with change (if everyone was a cleric). This is better than just splitting it 50/50 between two characters.

As with all chains, of course, there are weak links that you must cover up:

Weaknesses of strategy:

1. The cleric being hit will always take \$M/2\$ damage, even if they are not the last person in the chain. That is, if you hit the chain in the middle, the damage only propagates downward, not upward, along the series.
2. The first cleric who cast the spell does not have resistance to anything. As such, it would be smart to have the Barbarian/Cleric multiclass be the first cleric of this chain.
3. Concentration is difficult to maintain for spellcasters since anyone getting hit means a concentration save for everyone maintaining concentration spells.

Fun Quirks:

1. Your party is resistant to AoE attacks. If everyone (all \$N\$ clerics) gets hit with AoE damage, it will trickle down for everyone. If the AoE was supposed to deal \$M\$ damage and everyone failed their saves, then any given cleric will take:

   N: \$M/2\$ = \$M/2\$

   N-1: \$M/2 + (M/2)/2\$ = \$3M/4\$

   N-2: \$M/2 + (M/2 + (M/2)/2)/2\$ = \$7M/8\$

   N-3: \$M/2 + (M/2 + (M/2 + (M/2)/2)/2)/2\$ = \$15M/16\$

   N-a, where \$a\$ is distance from last person in the chain, starting at 0 and ending at \$N-1\$: $$M * {2^{a+1}-1\over 2^{a+1}}$$

   This means, the maximum damage you can take is \$M\$ if and only if everyone of your party fails their save. If someone succeeds on their save, that reduces the damage you will take, assuming you're down the chain (which, as a squishy, you should be).

2. An enemy cleric cannot break the chain by casting warding bond on a member of this chain, since it requires a "willing target". This safeguards you from a savvy enemy cleric who tries to break the entire chain at once (but you are still vulnerable to their Dispel Magic).

Shoring up the weaknesses:

1. Do not have the squishies be part of the chain. You, as the main cleric, focus on healing and other support spells. Allow the Barbarian, Rogue, and Paladin to arrange themselves in a warding bond chain. This way, anyone who takes damage as a result of being in this chain, would be able to withstand the full damage they would have taken anyway.
2. Put the Barbarian as the first caster of warding bond (cleric \$1\$), and have them be the face of the chain. They would receive all damage as they normally would -- that is, halved -- and the rest of the damage will be "lost" since there is nobody else down the chain to propagate it to.
3. Then, cleric \$2\$ must be the squishiest member of the chain. This ensures they will receive half damage if they are attacked directly, and throw the other half over to the tanky Barbarian, and they will also receive the least damage from a non-AoE spell if anyone further up the chain takes damage.
4. So, arrange the chain in this manner: ["Tankiest"]->["Squishiest"]->[2nd "squishiest"]->[2nd "tankiest"]
5. You may also use temp HP as any damage you receive from warding bond will have to go through the temp HP first.

I'll ignore the smell of cheese on this one, as this is a fun option to think about.

But what if you weren't all clerics?

If you can find rings of spell storing for each member of the party, you can store warding bond in each ring twice and (possibly) a healing word, so you can do the process noted above.

But in the absence of all of that, I'd advise you to apply this spell only to those that can take a quarter of the damage after resistance (such as the Rogue), to not apply it to party members who have it anyway (such as the Barbarian), and to have a lot of healing potions and healing scrolls at the ready!

Under this system, you only need to cast warding bond once.