Would allowing a character to gain bonuses for two shields be unbalanced?

Question

Would allowing a character to gain bonuses for two shields be unbalanced?

I have a character I've been working on who worships a god of protection. The idea is that he will use two shields, but the Player's Handbook states you can only gain a bonus from one.

Obviously, the character will be severely limited in terms of damage output (improvised/unarmed attacks like kicks and shield bashes only only). Will the increase in Armor Class (AC at first level with chainmail will be 20) overcome the limited attack bonuses and damage output of this character?

I plan to optimize at later levels with thing like the Sentinel feat to make this character able to protect the squishies.

Answer 1

Too good when your offense doesn’t need hands

In theory, giving up a hand for more defense could be a fair trade—if you were losing offensive capability in the exchange. But as Dan B’s answer details, that just isn’t the case for far too many classes, particularly one your character would be likely to gravitate towards naturally, the cleric.

But maybe we could avoid that

Maybe we can avoid the problems by giving up on the AC bonus of the second shield—but still having it be a meaningful part of the character.

Shield as a weapon

The rules do not allow cover bashing things with a “real” shield. There is precedent, however—in the Monster Manual—for shields as weapons. The lizardfolk has an attack called “spiked shield” that deals 1d6+Str damage. At the same time, the lizardfolk’s 15 AC is described as being due to “natural armor, shield.” The lizardfolk shaman on the next page has “AC 13 (natural armor),” and it does not have a shield in its statblock. So the implication here is that the spiked shield provides the usual +2 AC bonus that a regular shield does, as well as being available for an attack.

You can’t do that as a player character—there is no spiked shield in the rules, using a shield to do damage forces you to treat it as an improvised weapon (which makes it difficult to get proficiency and limits its available damage potential), and so on. However, what you might do—with DM permission—is treat the spiked shield as a weapon only. After all, the lizardfolk’s ability to use the spiked shield at the same time as their regular weaponry is due to their multiattack ability—and you don’t have that.

So you could ask to have a “shield” that is designed to be used as a weapon, with the stats of, say, a mace or morningstar, and no bonus to AC. Or maybe it could do 1d6 piercing or 1d4 bludgeoning, i.e. a die size smaller than those, but be resistant to disarming. Then you just use it as a regular weapon, but it pays the appropriate homage to your god.

A homebrew feat or fighting style might be appropriate here

If the cost of using two shields is just “gives up a free hand,” then it’s not balanced because you can do too much without needing hands. But if the cost is more than that—say, you need to get a fighting style from fighter or paladin, or you need to spend a feat—it might be more reasonable.

It’s too far out of scope here to try homebrewing something, but the Defense Fighting Style or the Dual Wielder feat might be well worth considering as a starting point. Consider that someone wearing armor, with a shield and a “fake weapon–shield,” could take the Defense Fighting Style for a +2 bonus to AC from the shield and a +1 bonus to AC from the fighting style—you could easily just flavor that as your “fake weapon—shield” being half as good as a “real” shield for defensive purposes. If you had a fighting style that required two shields—a stricter requirement than Defensive’s simple “wear armor” requirement—you might be able to justify a better benefit than that. A feat might be able to go even farther.

You can ask your DM for help working out the details and coming up with something acceptable to you both—and you can ask about those details, once you’ve decided on them, here, and we can judge whether or not you’ve hit the right sweet spot.

Answer 2

It's probably unbalanced

Here's an example: imagine a cleric who does most of their damage using spellcasting. Once this cleric has the War Caster feat (allowing them to cast spells while their hands are full), they'd always want to use two shields if that were legal.

The same is true of any other character that deals damage via spellcasting, but it's especially true for clerics and druids since they naturally get shield proficiency.

In particular, the character you're playing is going to feel strongly motivated to be some flavor of spellcaster, in order to have something to do while standing there with your high AC.

The bounded-accuracy theme of 5e means that even small improvements to AC can put you at unhittably-high Armor Class and should be seen as broken.

The DM shouldn't allow this.

Answer 3

For some builds this would not be unbalanced, but saying "you can gain a shield benefit from two shields" results in many problems.

First, any class that doesn't need a free hand to use a weapon or similar starts using two shields "for free". Second, when magic shields start arriving, stacking magic armor and two magic shields will make you reach unhittable ACs far sooner.

One approach might be to state "when you have two shields equipped and take the dodge action, you gain an additional +2 bonus to AC".

Realism wise, in practice, people who wanted better shield protection just got a larger shield instead of using two.

An approach I have seen is to have a larger than normal sized shield that interacts with the cover rules, such as:

Great Shield

A great shield is a larger, more bulky shield. Its weight is 3 times that of a standard shield. To use a great shield effectively, you must be proficient in heavy armor and have a Strength of at least 15; if you do not qualify, using a great shield reduces your movement speed by 10, and you cannot benefit from its additional features.

When you can use a great shield effectively, as a bonus action at the start of your turn you can brace for defence. In addition to its usual benefits, your shield grants half cover to you in one 90 degree arc in one direction, and attacks or effects on creatures that you would grant half cover to from the direction chosen instead suffer 3/4 cover.

In exchange, until the start of your next turn all of your attacks are at disadvantage, and any saving throws you cause are rolled at advantage, as blocking with your shield distracts you, and the cost of movement is doubled.