Is a custom race with an armour bonus based on two ability score modifiers imbalanced?

Question

I'm rolling my own races in D&D 5th Edition. As part of that I was thinking of introducing a racial trait modeled after the Monk's Unarmored Defense trait (with no shield bonus).

The race is naturally resistant to damage due to hardiness and the toughness of their rocky skin, so I figured instead of a bonus* I'd just give them the option of going armorless like a monk — without having to be a monk.

So their AC would be 10 + mod1 + mod2 .

I was thinking STR and CON for the modifiers (and prohibiting shields, per the Monk, though I'm not sure about that yet). The race also has resistance to fire, and +2 CON as a racial ability score bonus.

How does this compare to what the monk class can achieve over the 1–20 level span? Is this going to be unbalanced?

My main thought on abuse centers around the standard DEX build: DEX often increases your AC in a lot of situations. CON increases your HP. If I introduce a race that can increase both AC and HP with a single attribute, I fear that will be way more attractive than I want it to be.

^{* A bonus to AC would be easily abused by players because a generic bonus would stack with a lot of other AC bonuses. I don't want tanks to suddenly have a obvious must-pick race.}

Answer 1

This is really strong, at least for certain builds. Anyone who wanted to focus on Str anyway is likely to end up playing this race.

Firstly, Barbarians. Barbarians are currently one of the most MAD classes in 5e, needing good Str, good Con, and at least reasonable Dex. Your race would allow them to dump Dex and just focus on Str and Con.

Secondly, Druids. This is probably the worst case - your proposed race gives a Moon Druid an incredible boost to their Wild Shape forms. Str and Con are the strong points, and AC is the weak point, of most beasts, especially the ones Druids like to Wild Shape into.

Next, Fighters. This is the least problematic, since a Fighter could already afford to focus solely on Str and Con, but it does mean they end up with a better AC than they otherwise would have.

Oddly enough, it also enables Str-based Monk and Rogue builds. This isn't really a problem though, since in many ways Dex is inherently stronger than Str anyway.

Comparing it to Monk isn't really that useful, since they're essentially the same, but anyway:

• Level 1: Typical Monk has 16 Dex and 16 Wis, giving them an AC of 16. A Barbarian of your proposed race has 17 Con and 15 Str, giving them an AC of 15, or 17 with a shield.

• Level 4: Typical Monk has 18 Dex and 16 Wis, giving them an AC of 17. A Barbarian of your proposed race has 18 Con and 16 Str, giving them an AC of 17, or 19 with a shield.

• Level 8: Typical Monk has 20 Dex and 16 Wis, giving them an AC of 18. A Barbarian of your proposed race has 18 Con and 18 Str, giving them an AC of 18, or 20 with a shield.

• Level 12: Typical Monk has 20 Dex and 18 Wis, giving them an AC of 19. A Barbarian of your proposed race has 18 Con and 20 Str, giving them an AC of 19, or 21 with a shield.

• Level 16: Typical Monk has 20 Dex and 20 Wis, giving them an AC of 20. A Barbarian of your proposed race has 20 Con and 20 Str, giving them an AC of 20, or 22 with a shield.

Your proposed race can always have a better AC than a Monk of the same level if they choose, despite the inherent weakness of starting with +2 in a single stat rather than +1 in two stats.

You're right that basing it off Dex and Con would be even stronger, but only because Dex is inherently stronger than Str. Your footnote about bonuses, however, is less accurate. A minor bonus to AC, while good for everyone, is hardly a game-changer. Your proposed feature, on the other hand, can form the foundation of a build. It replaces a core feature of the Barbarian or Monk, and is effectively completely free, especially since your proposed race has fire resistance on top of it.

Answer 2

In my opinion, Unarmored Defense: STR+CON* would be slightly stronger than Mage Armor, but not unbalanced.

*(while not using shields or armor)

Unarmored Defense in general is relatively weak compared to mundane armor proficiencies. For example, say a character starts with a 16 in both Unarmored Defense attributes. That gives them 16 AC - the best starting AC possible. Compared to other armors:

• Mage Armor & 16 DEX: 16 AC
• Light Studded Leather & 16 DEX: 15 AC
• Medium Scale Mail & 14 DEX: 16 AC
• Heavy Chain Mail: 16 AC

So at level one, unarmored defense is, in the best case, equal AC to most other armor proficiencies.

However, Unarmored Defense falls behind later on. Medium and Heavy armor users can purchase armor upgrades with gold, while Unarmored Defense users must spend their ability score increases to keep up. Furthermore, if this Unarmored Defense is patterned on the Monk's ability, it prevents the use of a shield, putting it another 2 points behind for those classes who can use shields.

The presence of Magic Armor puts Unarmored Defense even further behind, because magic items which boost unarmored AC require attunement, while basic magic armor does not. Furthermore, Unarmored Defense requires that the player spend all their ASIs to keep their AC up, preventing them from taking Feats.

The specific ability scores tied to Unarmored Defense make a difference. Weapons which use Strength exclusively tend to be more powerful than Finesse weapons, so having Strength in Unarmored Defense will give the character a slight damage bonus. Also important to consider is how many ability scores the class as a whole will need. A Barbarian, for example, requires three ability scores: Strength, Dexterity, and Constitution. The Barbarian, however, can use a Shield.

By level 20, a character can reach 10 + 5 + 5 = 20 AC if they spend four out of five ASIs to improve their Unarmored Defense attributes. At that point their AC is equal to Full Plate + Shield. So while Unarmored Defense may produce somewhat high AC, it requires a huge investment, and precludes the use of many feats.

One of the clearest comparisons is to Mage Armor: 13 + DEX. Since a character using Unarmored Defense: STR + CON will probably start with a +3 ability mod from CON, and then not increase CON until level 16, when they've reached 20 Strength, the two features are almost equivalent for most of the game. Almost, because Strength allows the character to use stronger weapons than Dexterity.

So in conclusion, if you can account for the stronger weapons that become available due to tying AC to Strength, then yes the feature is balanced. Or maybe you're a DM that gives out magic armor, in which case Unarmored Defense is underpowered. Either way I don't see any way that this feature could be exploited for something all that much more powerful than what an ordinary character could achieve.

Answer 3

It can be made workable. Remembering that different methods of base AC don't stack...

At present it's Pick whichever one you're eligible for that provides the best:

• Light Armor: 10-12 + DexMod +SHield
• Medium Armor: 13-15 + (lower of +2 or DexMod) +Shield
• Heavy Armor: 14-18 + Shield
• Monk Unarmored: 10+ DexMod+WisMod (Possibly plus shield)
• Barbarian Unarmored: 10 + DexMod + ConMod (Possibly plus shield)
• Several spells: 13 + Caster'sMod
• Certain humanoid monsters: (11, 12 or 13)+ DexMod

Warforged get a +1 to worn - which is a massive bonus.

Shields, at present, are simply +2 to AC. The Shield Spell is +5 to any of the above.

On to the speculation

A second attribute, if it doesn't count with worn armor, ranges from +1 to +5, and thus scales with level.

If the attribute pair is Dex & Con, it's possible for it to get to AC 23 if they are barbarians, but Barbarians can do that anyway. Any other class is able to get to AC 20.

If it uses Dex & Str, again, it's overloading the overlap, but in this case, provides a real benefit to Barbarians... a barbarian will start usually with higher Str than Con, in order to do more damage (relying upon Rage to reduce damage taken), and Equal after 4th; this allows them to focus upon Str alone until Str 20; and so means no forced tradeoff between Damage and AC.

If the pairing is Dex + Int or Dex + Cha, it's essentially better than mage armor for casters of that attribute, because at 4th, they're typically going to be +4 from int, and thus better than mage armor.

A Dex + Wis is directly comparable to monks; it negates one of the key elements of the monk. So, it's not benficial to monks, but since Wis is a key secondary for many.... Also, there's the Clerics and Druids; it's going to be better than Barkskin, often right out the gate at First level.

If It Stacks with Worn

A +1 to AC that stacks with worn armors is a major bonus - comparable to a Ioun Stone of Protection!

The potential +5 to AC is better than ANY magic armor. It's game breaking.