When detractors talk about Dungeons & Dragons as a broken system, one of the most common things they point out is the abstract combat system. While the game has evolved into a more tactical system over the years, certain elements of the D&D combat engine have remained static. Most notably, hit points and armor class rolls remain as abstract as ever. While THAC0 came and went, attacks of opportunity showed up at the door, and feats changed the way people look at the fighter, hit points and armor class have stayed the same since the game’s inception. Oh, sure, AC has gone from being a “lower is better” system to a more intuitive “the higher the better” mechanic, and hit points for PCs and monsters alike have generally increased, but the essence of those rules remains the same. Armor class is a number that determines how untouchable you are; if someone beats it, you’re in trouble. If they can’t make the roll, the attack misses, no matter what. Hit points remain this magical threshold of damage, where your character can function perfectly as long as he has at least one left. Through three decades, six editions (counting the original brown box and the basic/expert/companion/master D&D boxed sets), and countless revisions, these elements of combat have remained all but untouched by time and designers alike. Strangely, though, hit points and armor class have also been one of the favorite whipping boys of the game in all its incarnations and spinoffs, be it D&D, AD&D, Castles & Crusades, Hackmaster, or what have you.
When a system stays in place that long, it usually means either one of two things: the mechanic is simply too good to let go, or no one has figured out a better way of doing things. Given the number of people who despise the sacred cows of hp and AC, I would assume it’s the latter in this case. Other systems have been tried out in the game, including variants like armor as damage reduction and vitality/wound points that were introduced in the 3.5 version of Unearthed Arcana. But for some reason, none of these more “realistic” systems have managed to rise above the level of optional rules. The ease of hit points and armor class keeps them in use, despite their abstract nature.
The Myth about hp and AC
One reason a lot of people detest hit points and armor class is because they buy into certain myths about those rules. The myth about armor class is that a higher AC makes a character harder to hit. The myth about hit points is that it is an absolute measurement of the physical damage a character can take before dying.
Armor class does not make a character harder to hit. It makes them harder to injure. That’s why there are so many things that modify it, from Dexterity bonuses to feats and magical items to simple armor. Wearing a suit of plate mail doesn’t make a person more difficult to hit; if anything, it makes them easier to hit. However, you can bash away at plate mail all you want and never make a dent, because it’s designed to keep a person’s vitals protected. Armor class is an amalgamation of everything that makes a character harder to hurt. When someone misses on a hit roll, any number of things is happening. The target could flat out dodge the blow. His armor could soak up the brunt of the attack. Maybe he’s a big burly half-orc and he just lets someone punch him in the gut, knowing that he’s so strong that the blow won’t even hurt him. Maybe he’s a skilled martial artist and he rolls with the blow. If the character has regeneration, maybe he actually lets himself take a nick or a scratch, but the wound is so small that it heals instantly. What exactly happens is up to the DM to decide. The more flavor he puts into the individual attack, the better. But making an attack roll is not really as simple as saying, “You hit,” or, “You miss.”
In some editions, Armor Class and Damage Reduction became somewhat blurred. If AC represents how hard it is for someone to get hurt, what’s the point of DR, which seems to cover the same purpose? The difference between armor class and damage reduction is that characters with a high armor class can still be hurt. Even a kobold can scratch a dragon if he gets lucky enough (i.e., rolls a natural 20). Damage Reduction takes luck out of the equation for the most part. A creature with DR 20/+1 will never get hurt by a longsword, no matter how lucky the wielder gets. That creature could dragon the blade across any part of his body, and it would never harm him. Armor Class is different, because there is always a chance that a lucky hit will find the weak spot in armor, or that even the best acrobat will make a wrong step and take a wound.
Like Armor Class, hit points represent many things and require some DM adjudication to determine their exact nature. Hit points are more than a measure of physical health. They are also a measurement of fatigue, luck, and endurance. Hit points don’t represent how many times you can be hit; they represent how much punishment of any kind you can take before dying. Hit points can be lost through taking cuts and bruises. They can be a reflection of a character’s body wearing down during a battle, or of accidental missteps that lead to a twisted ankle. Hit points can also reflect a blow where armor soaks most of the damage, because just because armor blocks a serious wound doesn’t mean the wearer doesn’t feel any impact.
It’s a DM’s job to decide how hit points are lost. The better a job a DM does of it, the less abstract the system seems. D&D, like all role-playing games, is partly a storytelling medium. As the narrator, it’s the DM’s job to make that story feel real. In the case of hit point loss, it’s a good idea to keep an eye on the severity of the hit, the damage roll, and how many hit points a character has left. Those factors, among others, should determine how the situation gets described.
Combat Examples: Armor Class
To illustrate the points I’m trying to make, I’ll give a few examples of how armor class can work without being reduced to a simple matter of hitting or missing.
Example #1: Gothren is a clumsy low-level wizard who has been separated from his companions in a dungeon. Knowing he’s in danger, he casts mage armor on himself for protection, and tries to creep through the dungeon as quietly as he can. Unfortunately, he’s not nearly quiet enough, and an orc overhears him. Combat begins. Gothren has a Dexterity of 6, which makes his AC with mage armor a 12. The orc rolls a 14 with his attack roll, hitting Gothren. The air around the wizard trembles as the orc’s falchion pushes past his magical defenses. Gothren tries to dodge the blade, but trips over his own feet and actually stumbles into the deadly weapon.
Example #2: Kyra is a nimble swashbuckling rogue in the midst of a battle on a pirate ship. One of the buccaneers dueling with her attacks from her flank with a rapier and rolls a critical hit. While dealing with a melee, one of the pirates nearly blindsides Kira with an attack. In an attempt to dodge, she hops onto the railing, only to find that she has no maneuvering room without diving into shark-infested waters. With nowhere to dodge, not even Kyra can avoid the blow, and she takes the wrong end of the rapier’s edge.
Example #3: Fal, a mace-wielding cleric, finds himself in a fight against an ogre. He swings his weapon, and his player rolls a 12 on the attack. The ogre’s AC is 16, so the attack misses. Since the ogre is a large, slow creature, it doesn’t seem likely that he’d just dodge the blow. So instead the creature just leans into it, turning his body so the attack hits its hard calloused hide rather than a vital spot. The ogre gives a grunt, but isn’t fazed by the attack at all. His hide armor and tough skin have absorbed all the damage.
Combat Examples: Hit Points
Actually determining how the hit happens is only one part of the matter. Here’s a continuation of the above examples, dealing with how each of the characters in question handles hit point loss.
Example #1: Gothren is not too lucky against the orc. The DM rolls maximum damage for the falchion’s hit, and Gothren loses 12 hit points. As a 1st-level wizard, he only has 4 hit points, so now he’s hovering on death’s door at -8hp. Gothren stumbled into the blade and got run right through by the orc. He’s now lying on the floor of the dungeon, unconscious, and it will take a miracle to save him.
Example #2: The DM rolls damage for the critical hit that the pirate scored on Kyra. He rolls a 1, which doubles to only 2 points of damage. Kyra has 30 hit points, so this critical hit turns out to be nothing more than a scratch. Even backed into a corner, she’s so nimble that she twists around and rolls with the blow, turning what could have been fatal damage into a minor scratch. The blade cuts past one of the straps of her leather armor, and leaves only a tear in her clothing. She’s practically unharmed, but a little more fatigued from her frantic dodge to avoid a life-threatening wound. Her slightly reduced hit points show that she won’t be as lucky next time, and might not have enough energy left to make such a magnificent dodge again.
Example #3: Fal’s attack did nothing against the ogre, and now the monster fights back. The ogre attacks and hits Fal, doing 15 points of damage. Fal has 36 hit points, so the damage done is pretty major. He isn’t particularly dexterous, and is slowed down even more by his plate mail and large shield. When he sees the ogre attack, he braces himself and readies his shield to defend. But he underestimated the ogre’s strength. While the shield does block the blow, the ogre’s massive club pushes Fal’s shield arm back, pinning it against his armor. Fal hears a crack in his arm as one of his broke breaks under the force, and the impact of the blow sends him staggering back a few steps. Armor doesn’t block everything…
The D&D combat system is an abstract system designed to speed along game play. Because of its abstract nature, that leaves a lot of space for the DM to fill in the blanks. While some consider the system to be a weakness, it can be a strength in the hands of the right DM. The key is to realize that the nature of the system requires extra description. Unlike some games which have hit location charts, damage by body area, and so on, D&D relies on the players and the DM to imagine what is happening in game, making sense of abstract numbers. By fleshing out the descriptions in combat and giving a few moments of thought into an attack, combat rolls can go from, “You hit and do 12 points of damage,” to, “You knock the orc off balance with the flat of your blade. In the split second when he’s trying to regain his balance, you double back and catch him with the edge right at the base of his skull.”