Rules

## Exceptions Supersede General Rules

General rules govern each part of the game. For example, the combat rules tell you that melee weapon attacks use Strength and ranged weapon attacks use Dexterity. That's a general rule, and a general rule is in effect as long as something in the game doesn't explicitly say otherwise.

The game also includes elements-class features, spells, magic items, monster abilities, and the like-that sometimes contradict a general rule. When an exception and a general rule disagree, the exception wins. For example, if a feature says you can make melee weapon attacks using your Charisma, you can do so, even though that statement disagrees with the general rule.

## Round Down

Whenever you divide or multiply a number in the game, round down if you end up with a fraction, even if the fraction is one-half or greater.

## Advantage and Disadvantage

Even if more than one factor gives you advantage or disadvantage on a roll, you have it only once, and if you have advantage and disadvantage on the same roll, they cancel each other.

## Combining Different Effects

Different game effects can affect a target at the same time. For example, two different benefits can give you a bonus to your Armor Class. But when two or more effects have the same proper name, only one of them (the most powerful one if their benefits aren't identical) applies while the durations of the effects overlap. For example, if bless is cast on you when you're still under the effect of an earlier bless, you gain the benefit of only one casting. Similarly, if you're in the radius of more than one Aura of Protection, you benefit only from the one that grants the highest bonus.

## Reaction Timing

Certain game features let you take a special action, called a reaction, in response to some event. Making opportunity attacks and casting the shield spell are two typical uses of reactions. If you're unsure when a reaction occurs in relation to its trigger, here's the rule: the reaction happens after its trigger completes, unless the description of the reaction explicitly says otherwise.

Once you take a reaction, you can't take another one until the start of your next turn.

## Resistance and Vulnerability

Here's the order that you apply modifiers to damage:

1. any relevant damage immunity,
2. any addition or subtraction to the damage,
3. one relevant damage resistance, and
4. one relevant damage vulnerability.

Even if multiple sources give you resistance to a type of damage you're taking, you can apply resistance to it only once. The same is true of vulnerability.

## Proficiency Bonus

If your proficiency bonus applies to a roll, you can add the bonus only once to the roll, even if multiple things in the game say your bonus applies. Moreover, if more than one thing tells you to double or halve your bonus, you double it only once or halve it only once before applying it. Whether multiplied, divided, or left at its normal value, the bonus can be used only once per roll.

## Bonus Action Spells

If you want to cast a spell that has a casting time of 1 bonus action, remember that you can't cast any other spells before or after it on the same turn, except for cantrips with a casting time of 1 action.

## Concentration

As soon as you start casting a spell or using a special ability that requires concentration, your concentration on another effect ends instantly.

## Temporary Hit Points

Temporary hit points aren't cumulative. If you have temporary hit points and receive more of them, you don't add them together, unless a game feature says you can. Instead, you decide which temporary hit points to keep.

## Falling

Falling from a great height is a significant risk for adventurers and their foes. The rule given in the player's handbook is simple: at the end of a fall, you take 1d6 bludgeoning damage for every 10 feet you fell, to a maximum of 20d6. You also land prone, unless you somehow avoid taking damage from the fall. Here are two optional rules that expand on that simple rule.

### Rate of Falling

The rule for falling assumes that a creature immediately drops the entire distance when it falls. But what if a creature is at a high altitude when it falls, perhaps on the back of a griffon or on board an airship? Realistically, a fall from such a height can take more than a few seconds, extending past the end of the turn when the fall occurred. If you'd like high-altitude falls to be properly time-consuming, use the following optional rule.

When you fall from a great height, you instantly descend up to 500 feet. If you're still falling on your next turn, you descend up to 500 feet at the end of that turn. This process continues until the fall ends, either because you hit the ground or the fall is otherwise halted.

### Flying Creatures and Falling

A flying creature in flight falls if it is knocked prone, if its speed is reduced to 0 feet, or if it otherwise loses the ability to move, unless it can hover or it is being held aloft by magic, such as the fly spell.

If you'd like a flying creature to have a better chance of surviving a fall than a non-flying creature does, use this rule: subtract the creature's current flying speed from the distance it fell before calculating falling damage. This rule is helpful to a flier that is knocked prone but is still conscious and has a current flying speed that is greater than 0 feet. The rule is designed to simulate the creature flapping its wings furiously or taking similar measures to slow the velocity of its fall.

If you use the rule for rate of falling in the previous section, a flying creature descends 500 feet on the turn when it falls, just as other creatures do. But if that creature starts any of its later turns still falling and is prone, it can halt the fall on its turn by spending half its flying speed to counter the prone condition (as if it were standing up in midair).

## Sleep

Just as in the real world, D&D characters spend many hours sleeping, most often as part of a long rest. Most monsters also need to sleep. While a creature sleeps, it is subjected to the unconscious condition. Here are a few rules that expand on that basic fact.

### Waking Someone

A creature that is naturally sleeping, as opposed to being in a magically or chemically induced sleep, wakes up if it takes any damage or if someone else uses an action to shake or slap the creature awake. A sudden loud noise-such as yelling, thunder, or a ringing bell-also awakens someone that is sleeping naturally.

Whispers don't disturb sleep, unless a sleeper's passive Wisdom (Perception) score is 20 or higher and the whispers are within 10 feet of the sleeper. Speech at a normal volume awakens a sleeper if the environment is otherwise silent (no wind, birdsong, crickets, street sounds, or the like) and the sleeper has a passive Wisdom (Perception) score of 15 or higher.

### Sleeping in Armor

Sleeping in light armor has no adverse effect on the wearer, but sleeping in medium or heavy armor makes it difficult to recover fully during a long rest.

When you finish a long rest during which you slept in medium or heavy armor, you regain only one quarter of your spent Hit Dice (minimum of one die). If you have any levels of exhaustion, the rest doesn't reduce your exhaustion level.

### Going without a Long Rest

A long rest is never mandatory, but going without sleep does have its consequences. If you want to account for the effects of sleep deprivation on characters and creatures, use these rules.

Whenever you end a 24-hour period without finishing a long rest, you must succeed on a DC 10 Constitution saving throw or suffer one level of exhaustion.

It becomes harder to fight off exhaustion if you stay awake for multiple days. After the first 24 hours, the DC increases by 5 for each consecutive 24-hour period without a long rest. The DC resets to 10 when you finish a long rest.