Roleplaying Games | Game Mechanics
What is the Lowest AC in 5e D&D?
Normally, in Dungeons and Dragons, players focus on crafting characters that are strong and effective in a variety of situations. There are varying extremes of this — some build characters with a technique called min-maxing, while others engage in power gaming. But D&D is also about having fun and experimenting, and sometimes that can involve an exercise in making the worst character — or at least being the worst in a very specific way.
To this end, I wanted to look at what designing a character with the lowest AC possible would entail.
For those unfamiliar, AC is armour class. In simple terms, that’s the number someone needs to meet on an attack roll in order to hit you. There are a variety of ways to increase AC — wearing certain armour, carrying a shield, equipping magic items that buff AC, or casting spells like Mage Armour or even Haste. By the same logic, there are ways to lower AC. The simplest way would be to wear no armour or buffing items, but your character class can play a role, too.
A character with no armour will generally calculate their AC with this formula: 10 + Dexterity modifier. For example, a character with a Dexterity modifier of +2 would have an AC of 12, and someone with a modifier of -2 would have an AC of 8. But some classes add two modifiers to the AC when unarmoured: Barbarians add Dexterity and Constitution, and Monks add Dexterity and Wisdom. If both those modifiers are negative, that’s going to drop the AC even lower than if it’s calculated merely with Dexterity.
This is where things can get a bit interesting. Modifiers are determined by ability scores. In the previous example, a Dexterity modifier of +2 indicates a Dexterity ability score of 14, while a modifier of -2 indicates an ability score of 6. Using the Ability Scores and Modifiers table in the Players’ Handbook (PHB), logically the lowest possible AC would come from having a Monk or Barbarian with both AC-effecting stats at 1 for modifiers of -5, generating an AC of 0.
But this isn’t possible by the way the rules are written in the PHB. If players handpick their stats, they have to use the Ability Score Point Cost table. The lowest ability score allowed on this table is 8, making the modifier -1 for both relevant stats and the AC 8.
The other option is to roll for stats. The PHB says players must roll 4 six-sided dice for each ability score, making the lowest possible score 4. The modifier here would be -3 and the AC would be 4. However, the odds of rolling four 1s for a stat are pretty low, and it’s even more unlikely to do this for two stats.
This doesn’t preclude homebrew rules for generating ability scores, of course, so it’s not impossible to create a character with an AC of 0, as long as you find a DM and party with a good sense of humour. This also doesn’t account for the possibility of having Slow cast on your character to reduce AC by another -2 or your character carrying a cursed item that semi-permanently reduces their AC in some way. Theoretically, it’s even possible to create a character with an AC below 0 in some situations, though I’m not sure how that would work in combat and if it would effectively be any different than an AC of 0.
In any case, there are certainly a variety of options at hand for creating a character with a hilariously low AC. With the right party, it could make for some fun adventures — though don’t expect to live for long.
References:
Cordell, Bruce R., Jeremy Crawford, Robert Schwalb, and James Wyatt. 2014. Player’s Handbook. Renton, WA: Wizards of the Coast LLC.
Thomas, Kyle. 2017. “D&D Philosophy — Power Gaming, Why It Sucks and Why You Need It — For Those About to Roll, We Salute You!” Pop Geeks. Retrieved January 31, 2020 (https://popgeeks.com/dungeons-dragons-power-gaming/).
Wiki Contributors. “Min-Maxing.” Giant Bomb. Retrieved January 31, 2020 (https://www.giantbomb.com/min-maxing/3015-128/).