Ability Checks

Skill Checks

Ability Score	Associated Skills
Strength	Athletics
Dexterity	Acrobatics, Sleight of Hand, Stealth
Constitution	N/A (See Con Table)
Intelligence	Arcana, History, Investigation, Nature, Religion
Wisdom	Animal Handling, Insight, Medicine, Perception, Survival
Charisma	Deception, Intimidation, Performance, Persuasion

Difficulty Classes

Task Difficulty	DC
Trivial	5
Easy	10
Moderate	15
Hard	20
Very Hard	25
Nearly Impossible	30

Ability Scores

Ability Modifiers
Score	Modifier	Score	Modifier
1	-5	16-17	+3
2-3	-4	18-19	+4
4-5	-3	20-21	+5
6-7	-2	22-23	+6
8-9	-1	24-25	+7
10-11	+0	26-27	+8
12-13	+1	28-29	+9
14-15	+2	30	+10

Strength: Strength measures bodily power and athletic training.

Strength	Used For...	Rule
Score	Determines modifier	Refer to this chart
	Carrying Capacity	Strength score times 15 in pounds²
	Push, Drag, or Lift	Up to 2 times carrying capacity²
Modifier	Determines bonus to strength related rolls	Refer to this chart
Save	Opposing a force that would physically move or bind you	1d20 + STR mod + Proficiency (if proficient)
Strength Check	Any attempt to lift, push, pull, or break something, to force your body through a space, or to otherwise apply brute force to a situation.	1d20 + STR mod
	Breaking Manacles	DC 20 check
	Breaking Rope	DC 17 check
Other possible uses	Force open a stuck, locked, or barred door. Push through a tunnel that is too small. Hang on to a wagon while being dragged behind it. Tip over a statue. Keep a builder from rolling.

² For each size category above medium, double the creatures carrying capacity and the amount it can pull, drag, or lift. For a tiny creature, half these weights.
² While pushing or dragging weight in excess of your carrying capacity, your speed drops to 5 feet.

Strength Skills: Below are all the skills associated with the Strength ability.

Athletics¹
Automatic	Climb a wall with plenty of handholds or a secure, knotted rope or rope ladder; swim in relatively calm water; jump a number of feet horizontally equal to half of your Strength score, or your full Strength score with a 10 foot running start; leap into the air a number of feet equal to half of (3 + your Strength modifier), or the full amount with a 10 foot running start ²
Easy	Climb a wall lacking an adequate amount of handholds, tread water in rough conditions, jump a few feet farther than you normally could; during a long jump, clear an obstacle such as a low-lying hedge or wall of height ≤a fourth of the jump's distance
Moderate	Climb a rope dangling from a protrusion or overhang (i.e. lacking a vertical surface to brace against), swim in rough water or against a mild current
Hard	Climb a wall with very few handholds, catch yourself on a rope or other handhold in the middle or at the end of your jump, swim in violent water or against a strong current
Very Hard	Climb a slippery or sheer wall with little or no handholds, climb vertically along an overhang with adequate handholds, swim in stormy waters
Feats of Strength - Other
Easy	Force open a stuck or broken door, break free from weak bindings, pull a stuck or wedged object loose
Moderate	Break through a wooden door reinforced with iron, hang on to a wagon while being dragged behind it
Hard	Break through a heavy locked or barred door, topple a stone statue
Very Hard	Break through a heavy, reinforced door such as a prison or armory door, hold a door shut against a room filling with water

¹ A PC can climb and swim under normal conditions without having to make a check; however, strenuous conditions may require that they pass an Athletics check. Each foot of movement during such a check costs an extra foot of movement, or an extra 2 feet if it is considered difficult terrain. Characters with climb and swim speeds ignore the extra costs associated with movement of this type. Similarly, the horizontal and vertical distance a PC can jump without having to make a check is determined by their Strength score and modifier respectively. An Athletics check is generally only required when attempting to jump a distance farther than the amount calculate in the table above.
² During a vertical jump a PC can extend their arms in order to achieve an extra distance equal to 1⁄2 of their height, which they can effectively add to their jump distance in order to attempt to grab on to a ledge or other handhold.

Dexterity: Dexterity measures agility, reflexes, and balance.

Dexterity	Used For...	Rule
Score	Determines modifier	Refer to this chart
Modifier	Determines bonus to Dexterity related rolls	Refer to this chart
	Armor Class	Certain types of armor add all or some of your DEX mod to your AC
	Initiative	1d20 + DEX mod
Save	Dodging out of harm's way	1d20 + DEX mod + Proficiency (if proficient)
Dexterity Check	Any attempt to move nimbly, quickly, or quietly, or to keep from falling on tricky footing	1d20 + DEX mod
	Lock picking (with thieves tools)	1d20 + DEX mod + Proficiency (if proficient)
Other possible uses	Control a heavily laden cart on a steep descent. Steer a chariot around a tight turn. Disable a trap. Securely tie up a prisoner. Wriggle free of bonds. Craft a small or detailed object.

² Certain types of medium and heavy armor add disadvantage to this roll.

Dexterity Skills: Below are all the skills associated with the Dexterity ability.

Acrobatics
Easy	Walk across an icy surface, stay upright in a turbulent situation, land safely on difficult terrain
Moderate	Walk along a narrow ledge, swing from a chandelier and land on your feet
Hard	Cross a wildly swaying rope bridge
Very Hard	Walk across a tightrope, vault over or under an enemy (through their space)
Sleight of Hand
Easy	Perform simple acts of legerdemain such as palming a coin-sized object
Contest (Perception)	Plant or steal an object on or from a target, conceal an object on your person
Stealth¹
Contest (Perception)	Conceal yourself from enemies, sneak past unsuspecting targets, slip away while others are distracted
Pick Lock² - Disarm Trap² - Other
Easy	Pick a simple lock, jam a simple trap, perform a task requiring particularly dexterous hands ³
Moderate	Pick a typical lock, escape from tight rope bindings, securely restrain a prisoner
Hard	Pick an elaborate lock, disarm a trap of average complexity, steer a chariot around a tight corner
Very Hard	Pick a masterwork lock, disarm a complex trap, escape from locked masterwork manacles

¹ Generally, becoming hidden in combat requires being heavily obscured or under total cover, but ultimately the rules leave it up to your personal adjudication.
² Proficiency with Thieves' Tools allows a player to add their proficiency bonus to checks made to open locks and disarm traps.
³ Such as Operation ^TM

Constitution¹: Constitution measures health, stamina, and vital force.

Constitution	Used For...	Rule
Score	Determines constitution modifier	Refer to this chart
Modifier	Determines bonus to constitution related rolls	Refer to this chart
	Holding your breath	Survive for minutes equal to 1 + CON mod (minimum 30 seconds), then survives for rounds equal to CON mod. Next turn drops to 0 HP and is dying.
	Going without food	Can go without enough food for days equal to 3 + CON mod. Each day past limit gain 1 level of exhaustion.
	Determining Hit Points	CON mod added to HP at each level
	Using Hit Dice	CON mod added to each hit dice used during short rest
Save	Endures a disease, poison, or other hazard that saps vitality	1d20 + CON mod + Proficiency (if proficient)
	Concentration	DC equal to greater of 10 or ½ of damage taken while concentrating on a spell
	Going without enough water	DC 15 or gain 1 level of exhaustion.
Check	Very rarely used, but can be used to push yourself beyond normal limits
Other possible uses	Quaff an entire stein of ale in one go.

Constitution Skills: Below are all the skills associated with the Constitution ability.

Concentration
Easy	Distracting environmental stimuli such as a wave crashing over the deck of a storm-tossed ship
Variable max(10,x)	After taking damage make a Constitution Saving throw with a DC of either 10 or half of the damage taken, whichever is higher.
Forced March
Variable DC 10+X	At the end of each hour a PC must make a Constitution saving throw with a DC equal to 10 + the number of hours traveled past 8. On a failed throw the PC advances one level of exhaustion.
Air
A PC can hold their breath for a number of minutes equal to 1 + their Constitution modifier (minimum 30 seconds). When out of breath, a PC can survive for a number of rounds equal to their Constitution modifier before they drop to 0 hit points and begin to die.
Food
A PC must eat one pound of food per day in order to subsist. They can go without food for a number of days equal to 3 + their Constitution modifier (minimum 1) before they begin to starve. This day count is reset when the PC eats their fill for a day; otherwise, the PC advances one level of exhaustion at the end of each day beyond their limit.
Water
Automatic	A PC drinking less than half the amount of water they require during the day advances one level of exhaustion at the end of the day, or two levels if they are already suffering from exhaustion.
Moderate	A PC drinking more than half the amount of water they require during the day but less than the full amount must succeed on a Constitution saving throw or advance one level of exhaustion, or two levels if they are already suffering from exhaustion.

¹ Constitution represents a largely passive set of 'skills' which have more to do with enduring than performing a specific action the PC can become proficient in. Therefore, Constitution checks are more uncommon than other ability checks and are usually made without adding a proficiency bonus, although situational bonuses may still apply. NOTE: An ability check is different from a saving throw; players can be proficient at Constitution saving throws.
² A PC can only travel for eight hours a day before they risk becoming exhausted.
³ A PC requires one gallon of water per day, or two if the climate is harsh.

Intelligence: Intelligence measures mental acuity, accuracy of recall, and the ability to reason.

Intelligence	Used For...	Rule
Score	Determines modifier	Refer to this chart
Modifier	Determines bonus to intelligence related rolls	Refer to this chart
Save	Disbelieving certain illusions and resisting mental assaults that can be refuted with logic, sharp memory, or both	1d20 + Ability mod + Proficiency (if proficient)
Check	Drawing on logic, education, memory, or deductive reasoning	1d20 + INT mod
Other possible uses	Communicate with a creature without words. Estimate the value of a precious item. Forge a document. Recall lore about a craft or trade. Win a game of skill.

Intelligence Skills: Below are all the skills associated with the Intelligence ability.

Arcana - History - Nature - Religion
Easy	Recall widely known information; identify common people, places, objects, symbols, fauna, or flora
Moderate	Recall more obscure or specific information; identify uncommon people, places, objects, symbols, fauna, or flora
Hard	Recall truly esoteric or precise information; identify rare people, places, objects, symbols, fauna, or flora
Very Hard	Recall information that is known only by a privileged few; identify exceedingly rare people, places, objects, symbols, fauna, or flora
Investigation - Other
Easy	Identify a particularly obvious trap or a secret or coded message left by a contact, communicate a simple idea with an intelligent creature you don't share a language with, discover the true nature of a low-level illusion.
Moderate	Identify a typical trap, determine time or cause of death of a recently deceased creature, estimate the material worth of an item, discover the true nature of a mid-level illusion
Hard	Identify a well-hidden trap, object, or area; forge a document or identify such a document, discover the true nature of a high-level illusion
Very Hard	Identify a magically-hidden trap, object, or area; discern the purpose and process of a complicated device or system; determine the integrity of a structure, construct, or formation and identify any exploitable weak points

Wisdom: Wisdom measures perceptiveness, intuition, and attunement with the surrounding world.

Wisdom	Used For...	Rule
Score	Determines modifier	Refer to this chart
Modifier	Determines bonus to wisdom related rolls	Refer to this chart
Save	Resisting effects that charm, frighten, or otherwise assault your willpower	1d20 + WIS mod + Proficiency (if proficient)
Check	Reading body language, understanding someone's feelings, noticing things about the environment, or caring for an injured person	1d20 + WIS mod
Other possible uses	Get a gut feeling about what course of action to follow. Discern whether a seemingly dead or living creature is undead.

Wisdom Skills: Below are all the skills associated with the Wisdom ability.

Insight - Perception
Easy	Spot a prominent landmark or structure in the distance, hear the far-off sound of thunder signaling a coming storm, determine if a child is telling the truth
Moderate	Spot a natural-obscured object or feature, eavesdrop on a conversation in the next room, discern who among a cagey group is the leader, discern the intended message of a non-verbal communication
Hard	Spot a well-hidden object or feature, eavesdrop on a hushed conversation through a heavy door, guess at the enemy's next action
Very Hard	Spot a nearly-invisible object or feature, read the lips of a creature you can see but not hear
Contest (Deception)	Determine if someone is lying or disguising themselves or their intentions
Contest (Stealth)	Spot a creature attempting to hide, hear the movements of a hidden foe
Survival
Easy	Follow a well-worn trail through a forest, follow the tracks of a creature through snow or mud, forage for a day's worth of food in a plentiful area, navigate on a clear night
Moderate	Follow an abandoned or forgotten trail, track a creature through a forest, forage for a day's worth of food in a sparse area, navigate on a cloudy night, predict an oncoming storm, identify the signs of nearby creatures
Hard	Track a creature over barren terrain, forage for a day's worth of food in a harsh area, navigate through an alien area on a cloudy night, predict tomorrow's weather
Very Hard	Track a creature after rainfall, navigate an alien area on a stormy night
Animal Handling - Medicine - Other
Easy	Calm a domesticated animal, stabilize a dying creature outside of combat, diagnose a common ailment
Moderate	Calm a wild but otherwise peaceful animal, intuit an animal's emotional state, set a broken bone, perform a complex maneuver while mounted, stabilize a dying creature in the middle of combat, diagnose an uncommon ailment
Hard	Intuit a hostile animal's next action, control an untrained mount, diagnose a rare ailment
Very Hard	Calm a dangerous wild animal, diagnose magical and divine ailments

Charisma: Charisma measures force of personality, persuasiveness, personal magnetism, social influence, and physical attractiveness.

Charisma	Used For...	Rule
Score	Determines modifier	Refer to this chart
Modifier	Determines bonus to charisma related rolls	Refer to this chart
Save	Withstanding effects, such as possession, that would subsume your personality or hurl you to another plane of existence	1d20 + WIS mod + Proficiency (if proficient)
Check	Trying to influence or entertain others, when you try to make an impression or tell a convincing lie, or when you are navigating a tricky social situation	1d20 + Ability mod
Other possible uses	Find the best person to talk to for news and gossip. Blend into a crowd to get the sense of key topics of conversation.

Charisma Skills: Below are all the skills associated with the Charisma ability.

Deception
Contest (Insight)	Fast-talk or con someone, adopt a disguise or impersonate another creature, tell a convincing lie or otherwise hide your true intentions
Intimidation
Easy	Scare a spineless noble in to handing over their coin purse
Moderate	Pry information out of an uncooperative prisoner, convince street thugs to back down from a confrontation
Hard	Advise a guard that it might be best to look the other way this time around, coerce an official in to signing a document
Very Hard	Frighten a creature larger than you, causing it to flee; stop an agitated mob in their tracks
Performance
Easy	Routine performance such as telling a story in a tavern or around a campfire
Moderate	Professional performance such as an inspiring speech or an impressive musical display which may attract the attention of a local troupe and lead to regional fame
Hard	Memorable performance which may attract the attention of a local patron and lead to national fame
Very Hard	Extraordinary performance which may attract the attention of distant patrons and even extraplanar beings
Persuasion
Easy	Convince the mayor to allow your party to help, calm a distraught person
Moderate	Persuade a group of highway thieves to leave in peace, convince a friendly acquaintance that you know best
Hard	Convince a chamberlain to let your party see the king, inspire or rally a crown of townsfolk, negotiate a peace between warring tribes
Very Hard	Convince a sphinx that you are worthy of the secrets it guards, assure a dragon you're worth more alive than dead

Combat

Conditions
Condition	Description
Blinded	A blinded creature can't see and automatically fails any ability check that requires sight. Attack rolls against the creature have advantage, and the creature's attack rolls have disadvantage.
Charmed	A charmed creature can't attack the charmer or target the charmer with harmful abilities or magical effects The charmer has advantage on any ability check to interact socially with the creature.
Deafened	A deafened creature can't hear and automatically fails any ability check that requires hearing.
Frightened	A frightened creature has disadvantage on ability checks and attack rolls while the source of its fear is within line of sight. The creature can't willingly move closer to the source of its fear.
Grappled	A grappled creature's speed becomes 0, and it can't benefit from any bonus to its speed. The condition ends if the grappler is incapacitated. The condition also ends if an effect removes the grappled creature from the reach of the grappler or grappling effect, such as when a creature is hurled away by the thunderwave spell.
Incapacitated	An incapacitated creature can't take actions or reactions.
Invisible	An invisible creature is impossible to see without the aid of magic or a special sense. For the purpose of hiding, the creature is heavily obscured. The creature's location can be detected by any noise it makes or any tracks it leaves. Attack rolls against the creature have disadvantage, and the creature's attack rolls have advantage.
Paralyzed	A paralyzed creature is incapacitated and can't move or speak. The creature automatically fails Strength and Dexterity saving throws. Attack rolls against the creature have advantage. Any attack that hits the creature is a critical hit if the attacker is within 5 feet of the creature.
Petrified	A petrified creature is transformed, along with an nonmagical object it is wearing or carrying, into a solid inanimate substance (usually stone). Its weight increases by a factor of ten, and it ceases aging. The creature is incapacitated, can't move or speak, and is unaware of its surroundings. Attack rolls against the creature have advantage. The creature automatically fails Strength and Dexterity saving throws. The creature has resistance to all damage. The creature is immune to poison and disease, although a poison or disease already in its system is suspended, not neutralized.
Poisoned	A poisoned creature has disadvantage on attack rolls and ability checks.
Prone	A prone creature's only movement option is to crawl, unless it stands up and thereby ends the condition. The creature has disadvantage on attack rolls. An attack roll against the creature has advantage if the attacker is within 5 feet of the creature. Otherwise, the attack roll has disadvantage.
Restrained	A restrained creature's speed becomes 0, and it can't benefit from any bonus to its speed. Attack rolls against the creature have advantage, and the creature's attack rolls have disadvantage. The creature has disadvantage on Dexterity saving throws.
Stunned	A stunned creature is incapacitated, can't move, and can speak only falteringly. The creature automatically fails Strength and Dexterity saving throws. Attack rolls against the creature have advantage.
Unconscious	An unconscious creature is incapacitated, can't move or speak, and is unaware of its surroundings. The creature drops whatever it's holding and falls prone. The creature automatically fails Strength and Dexterity saving throws. Attack rolls against the creature have advantage. Any attack that hits the creature is a critical hit if the attacker is within 5 feet of the creature.

Exhaustion
Level	Effect
1	Disadvantage on ability checks.
2	Speed halved
3	Disadvantage on attack rolls and saving throws
4	Hit point maximum halved
5	Speed reduced to 0
6	Death

Suffering Exhaustion
Cause	Details
Forced March	For each hour spent traveling past 8 hours make a CON save at DC 10 + 1 for each hour past 8. On a failed save, a character suffers 1 level of exhaustion.
Starvation	If a creature doesn't eat enough food in a day, they start to starve. Food can be stretched out by eating half as much per day, which counts as half a day without food. A character can go without food for a number of days equal to 3 + CON mod, and then at the end of each day beyond that a character automatically suffers 1 level of exhaustion. A normal day of eating reduces the days without food to 0.
Dehydration	A creature who drinks less than half as much water than they need in a day must succeed on a DC 15 CON save or suffer 1 level of exhaustion. A character with access to even less water automatically suffers 1 level of exhaustion at the end of the day. If a character already has any levels of exhaustion, they gain 2 levels in either case.
Barbarian's Frenzy	A Barbarian who goes down the Path of the Berserker can choose to enter a frenzy if he is raging. When the rage ends, he suffers a level of exhaustion.

Reducing Levels of Exhaustion
At the end of a long rest, provided a character has had enough food and water that day, they reduce their level of exhaustion by 1.

Damage Types
Type	Description
Acid	Corrosive substances, magical or alchemical
Bludgeoning	Blunt force hits (hammer, falling, etc.)
Cold	Extreme low temperature and magic attacks
Fire	Fire breaths and fire based spells and magic
Force	Pure magical energy focused in damaging form
Lightning	lightning bolt, or electricity spells.
Necrotic	Dealt by certain undead and corrupted magic
Piercing	Puncturing and impaling attacks and weapon
Poison	Venomous stings, spores, substances and gases
Psychic	Mental attacks and damage like psionic abilities
Radiant	Holy damage, like divine spells or creatures
Slashing	Swords, axes, and monster claws that slash
Thunder	Concussive burst of sound or shock wave

Damage Severity and Level
Character Level	Setback	Dangerous	Deadly
1st-4th	1d10	2d10	4d10
5th-10th	2d10	4d10	10d10
11th-16th	4dl0	10d10	18d10
17th-20th	10d10	18d10	24d10

Cover
Cover Type	Effect
1/2 cover	+2 bonus to AC and Dexterity saving throws against attacks and effects that originate on the opposite side of the cover.
3/4 cover	+5 bonus to AC and Dexterity saving throws against attacks and effects that originate on the opposite side of the cover.
Full cover	Can't be targeted by an attack or a spell.

Actions In Combat
Action	Description
Attack	Make one¹ melee or ranged attack, a grapple, or a shove.
Cast a Spell	Casts a spell with a casting time of 1 action.
Dash	Gain extra movement equal to your speed for this turn, applying any modifiers.
Disengage	Your movement doesn't provoke opportunity attacks for the rest of the turn.
Dodge	Until the start of your next turn, any attacks against you are made with disadvantage provided you can see the attacker, and you have advantage on DEX saves. You lose this benefit if you are incapacitated or your speed drops to 0.
Help	Creature you help gains advantage on next ability check to perform the task you are assisting with, or help with attack roll if enemy is within 5 feet of you.
Hide	You make a stealth check. Details here.
Ready	Prepare to do something when a specific trigger occurs. Details here.
Search	Make either a perception or investigation check in an attempt to locate something.
Use an Object	Interacting with a second object on your turn (the first is free), or a more complicated object.
Climb onto a Bigger Creature²	Athletics or Acrobatics check opposed by creature's Acrobatics check. Details here.
Disarm²	Use an attack to make attack roll opposed by target's Athletics or Acrobatics check. Target has advantage if holding the item with 2 or more hands.
Mark²	When you make a melee attack and hit, you can mark them. Your opportunity attacks against the creature have advantage and don't expend your reaction, however you may only make 1 attack in this manner.
Overrun²	As an action or bonus action make Athletics check opposed by hostile's Athletics. If you win, you can move through the hostile's space once this turn.
Shove aside²	Use shove to push target to the side rather than away. Details here.
Tumble²	As an action or bonus action make Acrobatics check opposed by hostile's Acrobatics. If you win, you can move through the hostile's space once this turn.

¹ Certain features allow you to make more than one attack, grapple, or shove with this action.
² These actions are optional and can be found on pages 271-272 of the DMG.

The Rules of Stealth

When attempting to hide, there are 4 simple rules to remember.

1) If someone can see you, you can't attempt to hide from them.
2) Someone doesn't see you when they're not looking at you.
3) Once hidden, you can be detected via sight, hearing, or both, so don't be seen or heard. If their perception check or passive perception is higher than your stealth roll, they detect you.
4)You can hide in plain sight, given a moment of being unseen or unattended and an appropriate concealment strategy

If you are hidden, or when someone can't see you, you have advantage on attack rolls against them, and they have disadvantage on attack rolls against you. If you make an attack while hidden, regardless of whether it hits or misses, you are no longer hidden.

Grappling, Shoving, and Climbing onto Bigger Creatures

When you take the attack action you can use one attack to grapple, shove, or climb onto an enemy.

Grappling: You can grab a creature which is no more than one size category higher than you. Using at least one free hand, you make an Athletics check contested by the target's Athletics or Acrobatics check. If you succeed, the target is now grappled by you. You can also grapple an enemy to climb on top of it.
Escaping a grapple.: While grappled, a creature can use its action to make an Athletics or Acrobatics check opposed by your Athletics check. If the creature succeeds, it moves to a space next to you.
Moving a grappled creature.: When you move, you can drag or carry the grappled creature with you, but your speed is halved, unless the creature is two or more sizes smaller than you.
Shoving: Using the attack action, you can attempt to shove a creature no more than one size larger than you. You make an Athletics check opposed by its Athletics or Acrobatics check. If you succeed you either move it 5 feet in any direction or knock it prone.
Climbing onto Bigger Creatures: A suitably large creature can be treated as terrain for the purpose of jumping onto its back or clinging to a limb. Once you make any ability checks necessary to get into position and to get onto the bigger creature, the smaller creature uses its action to make an Athletics or Acrobatics check contested by the targets Acrobatics check. If it wins the contest, the smaller creature successfully moves into the target creature's space and clings to his body. While in the target's space, the smaller creature moves with the target and has advantage on attack rolls against it.
The smaller creature can move around within the larger creature's space, treating the space as difficult terrain. The larger creature may or may not be able to attack the smaller creature, depending on the smaller creature's location, this is up to the DM. The larger creature can try to dislodge the creature as an action - shaking it off, scraping it against a wall, grabbing and throwing it off - by making an Athletics check opposed by the smaller creature's Athletics or Acrobatics check.

Readying an Action

    As an action on your turn, you can take the Ready action so that you may act later in the round using your reaction. To do this, you need to clearly define 2 things.
    First, you must decide what circumstances will trigger your prepared action. For example, you could say that the trigger is "A hostile creature comes through the door in front of me".
    Second, you must decide what you will do if the triggering event happens. You may take an action such as the attack action or you may move up to your speed. For example, you could say "I will attack with my greatsword".
    When you put both the trigger and the action together you get a coherent sentence. The example is "If a hostile creature comes through the door in front of me, I will attack with my greatsword".
    Readying A Spell. When you ready a spell, you cast it as normal but hold its energy, which you then release with your reaction. To be readied a spell must have a casting time of 1 action, and holding onto the spell's magic requires concentration. If your concentration is broken the spell dissipates.

Dropping to 0 Hit Points

Death Saving Throws: When you start your turn at 0 hit points, you need to make a death saving throw. Rolling 9 and below counts as a failure, and 10 and above counts as a success. If you accrue 3 failures before 3 successes, you die. If you accrue 3 successes, you are stabilized. If you regain any hit points, both your successes and failures are reset.
Rolling 1 or 20.: When you make a death saving throw and roll a 1 on the d20, it counts as two failures. If you roll a 20 on the d20, you regain 1 hit point.
Damage at 0 Hit Points.: If you take any damage while you have 0 hit points, you suffer a death saving throw failure. If the damage is from a critical hit, you suffer two failures instead. If the damage equals or exceeds your hit point maximum, you suffer instant death.
Instant Death: Massive damage can kill you instantly. When damage reduces you to 0 hit points and there is damage remaining, you die if the remaining damage equals or exceeds your hit point maximum. For example, a cleric with a maximum of 12 hit points currently has 6 hit points. If she takes 18 damage from an attack, she is reduced to 0 hit points, but 12 damage remains. Because the remaining damage equals her hit point maximum, the cleric dies.
Falling Unconscious: If damage reduces you to 0 hit points and fails to kill you, you fall unconscious. This unconsciousness ends if you regain any hit points.
Stabilizing a Creature: The best way to save a creature with 0 hit points is to heal it. If healing is unavailable, the creature can at least be stabilized so that it isn't killed by a failed death saving throw. You can use your action to administer first aid to an unconscious creature and attempt to stabilize it, which requires a successful DC 10 Medicine check. A stable creature doesn't make death saving throws, even though it has 0 hit points, but it does remain unconscious. The creature stops being stable, and must start making death saving throws again, if it takes any damage. A stable creature that isn't healed regains 1 hit point after 1d4 hours.

Wild Magic

Immediately after you cast a sorcerer spell of 1st level or higher, the DM can have you roll a d20. If you roll a 1, roll on the Wild Magic Surge table to create a random magical effect.

Wild Magic Surge
d100	Effect
01-02	Roll on this table at the start of each of your turns for the next minute, ignoring this result on subsequent rolls.
03-04	For the next minute, you can see any invisible creature if you have line of sight to it.
05-06	A modron chosen and controlled by the DM appears in an unoccupied space within 5 feet of you, then disappears 1 minute later.
07-08	You cast fireball as a 3rd level spell centered on yourself.
09-10	You cast magic missile as a 5th level spell.
11-12	Roll a d10. Your height changes by a number of inches equal to the roll. If the roll is odd, you shrink. If the roll is even, you grow.
13-14	You cast confusion centered on yourself.
15-16	For the next minute, you regain 5 hit points at the start of each of your turns.
17-18	You grow a long beard made of feathers that remains until you sneeze, at which point the feathers explode out from your face.
19-20	You cast grease centered on yourself.
21-22	Creatures have disadvantage on saving throws against the next spell you cast in the next minute that involves a saving throw.
23-24	Your skin turns a vibrant shade of blue. A remove curse spell can end this effect.
25-26	An eye appears on your forehead for the next minute. During that time, you have advantage on Wisdom (Perception) checks that rely on sight.
27-28	For the next minute, all your spells with a casting time of 1 action have a casting time of 1 bonus action.
29-30	You teleport up to 60 feet to an unoccupied space of your choice that you can see.
31-32	You are transported to the Astral Plane until the end of your next turn, after which time you return to the space you previously occupied or the nearest unoccupied space if that space is occupied.
33-34	Maximize the damage of the next damaging spell you cast within the next minute.
35-36	Roll a d10. Your age changes by a number of years equal to the roll. If the roll is odd, you get younger (minimum 1 year old). If the roll is even, you get older.
37-38	1d6 flumphs controlled by the DM appear in unoccupied space within 60 feet of you and are frightened of you. They vanish after 1 minute.
39-40	You regain 2d10 hit points.
41-42	You turn into a potted plant until the start of your next turn. While a plant, you are incapacitated and have vulnerability to all damage. If you drop to 0 hit points, your pot breaks, and your form reverts.
43-44	For the next minute, you can teleport up to 20 feet as a bonus action on each of your turns.
45-46	You cast levitate on yourself.
47-48	A unicorn controlled by the DM appears in a space within 5 feet of you, then disappears 1 minute later.
49-50	You can't speak for the next minute. Whenever you try, pink bubbles float out of your mouth.
51-52	A spectral shield hovers near you for the next minute, granting you a +2 bonus to AC and immunity to magic missile.
53-54	You are immune to being intoxicated by alcohol for the next 5d6 days.
55-56	Your hair falls out but grows back within 24 hours.
57-58	For the next minute, any flammable object you touch that isn't being worn or carried by another creature bursts into flame.
59-60	You regain your lowest-level expended spell slot.
61-62	For the next minute, you must shout when you speak.
63-64	You cast fog cloud centered on yourself.
65-66	Up to three creatures you choose within 30 feet of you take 4d10 lightning damage.
67-68	You are frightened by the nearest creature until the end of your next turn.
69-70	Each creature within 30 feet of you becomes invisible for the next minute. The invisibility ends on a creature when it attacks or casts a spell.
71-72	You gain resistance to all damage for the next minute.
73-74	A random creature within 60 feet of you becomes poisoned for 1d4 hours.
75-76	You glow with bright light in a 30-foot radius for the next minute. Any creature that ends its turn within 5 feet of you is blinded until the end of its next turn.
77-78	You cast polymorph on yourself. If you fail the saving throw, you turn into a sheep for the spells duration.
79-80	Illusory butterflies and flower petals flutter in the air within 10 feet of you for the next minute.
81-82	You can take one additional action immediately
83-84	Each creature within 30 feet of you takes 1d10 necrotic damage. You regain hit points equal to the sum of the necrotic damage dealt.
85-86	You cast mirror image.
87-88	You cast fly on a random creature within 60 feet of you.
89-90	You become invisible for the next minute. During that time, other creatures can't hear you. The invisibility ends if you attack or cast a spell.
91-92	If you die within the next minute, you immediately come back to life as if by the reincarnate spell.
93-94	Your size increases by one size category for the next minute.
95-96	You and all creatures within 30 feet of you gain vulnerability to piercing damage for the next minute.
97-98	You are surrounded by faint, ethereal music for the next minute.
99-00	You regain all expended sorcery points.

Adventuring

Character Leveling Requirements
Experience Points	Level	Proficiency Bonus
0	1	+2
300	2	+2
900	3	+2
2,700	4	+2
6,500	5	+3
14,000	6	+3
23,000	7	+3
34,000	8	+3
48,000	9	+4
64,000	10	+4
85,000	11	+4
100,000	12	+4
120,000	13	+5
140,000	14	+5
165,000	15	+5
195,000	16	+5
225,000	17	+6
265,000	18	+6
305,000	19	+6
355,000	20	+6

Currency Exchange Rates
Coin	CP	SP	EP	GP	PP
Copper	1	1/10	1/50	1/100	1/1000
Silver	10	1	1/5	1/10	1/100
Electrum	50	5	1	1/2	1/20
Gold	100	10	2	1	1/10
Platinum	1000	100	50	10	1

Adventuring Services
Service	Pay
Coach Cab
Between Towns	3 cp/mile
Within a City	1 cp
Hireling
Skilled	2 gp/day
Unskilled	2 sp/day
Messenger	2 cp/mile
Road/Gate Toll	1 cp
Ship's Passage	1 sp/mile
First Level Spell¹	10-30gp + components
Second Level Spell¹	30-50gp + components
Third+ Level Spell²	How much ya got?³

¹ First and second level spellscasting services are easy enough to find in a decently sized city or town.
² Third level and higher spells are much more rare and can only be found with any amount of regularity in a large city, perhaps home to a University or Temple.
³ Often times a spellcaster might ask for a service rather than monetary payment.

Lifestyle Expenses
Lifestyle	Price/Day
Wretched	-
Squalid	1 sp
Poor	2 sp
Modest	1 gp
Comfortable	2 gp
Wealthy	4 gp
Aristocratic	10 gp minimum

Food, Drink, and Lodging
Item	Cost
Ale
Gallon	2 sp
Mug	4 cp
Banquet (per person)	10 gp
Bread, loaf	2 cp
Cheese, hunk	1 sp
Inn stay (per day)
Squalid	7 cp
Poor	1 sp
Modest	5 sp
Comfortable	8 sp
Wealthy	2 gp
Aristocratic	4 gp
Meals (per day)
Squalid	3 cp
Poor	6 cp
Modest	3 sp
Comfortable	5 sp
Wealthy	8 sp
Aristocratic	2 gp
Meat, chunk	3 sp
Wine
Common (pitcher)	2 sp
Fine (bottle)	10 gp

Map Travel Paces

Below are guidelines for traveling in different sized map areas at different paces (slow, normal, and fast.)

Dungeon
Slow Pace	Normal Pace	Fast Pace
20 sq./min	30 sq./min	40 sq./min
1 square = 10 feet

City
Slow Pace	Normal Pace	Fast Pace
2 sq./min	3 sq./min	4 sq./min
1 square = 100 feet

Province
Slow Pace	Normal Pace	Fast Pace
2 hexes/hour or18 hexes/day	3 hexes/hour or24 hexes/day	4 hexes/hour or30 hexes/day
1 hex = 1 miles

Kingdom
Slow Pace	Normal Pace	Fast Pace
1 hex/3 hours or3 hexes/day	1 hex/2 hours oror 4 hexes/day	1 hex/1.5 hours or5 hexes/day
1 hex = 6 miles

Travel Paces

Below are guidelines for how fast a PC can travel on foot in actual distances at different paces (slow, normal and fast.)

Fast
Minute	Hour	Day	Effect
400 ft	4 miles	30 miles	-5 to passive perception score

Normal
Minute	Hour	Day	Effect
300 ft	3 miles	24 miles	--

Slow
Minute	Hour	Day	Effect
200 ft	2 miles	18 miles	Able to stealth

Calculating Your Party's Pace
Minute	Hour	Day	Pace Effect
Speed X 10 ft.	Speed ÷10 mi.	Speed X 0.6 mi.	Effect based on pace

Pace Effects
Slow	Normal	Fast
Use 2/3 base speed, able to stealth	No effect	Use 1.33 base speed, -5 passive perception

Encounter Distances

Below are guidelines on when to start an encounter based on terrain, audible distances, and outdoor visibility.

Terrain	Encounter Distance
Arctic, desert, farmland, or grassland	6d6 x 10 feet
Forest, swamp, or woodland	2d8 x 10 feet
Hills or wastelands	2d10 x 10 feet
Jungle	2d6 x 10 feet
Mountains	4d10 x 10 feet

Audible Distance
Trying to be quiet	2d6 x 5 feet
Normal noise level	2d6 x 10 feet
Very loud	2d6 x 50 feet

Visibility Outdoors
Clear day, no obstructions	2 miles
Rain	1 mile
Fog	100 to 300 feet
From a height	x 20

Vision and Light
	Hindrance	Examples
Lightly Obscured	Disadvantage on Perception checks relying on sight	Dim light, patchy fog, moderate foliage
Heavily Obscured	Blinded condition	Darkness, opaque fog, dense foliage

Light Sources
Source	Bright Light	Dim Light	1 hour
Mundane Sources
Candle	5 feet	+5 feet	6 hours
Lamp	15 feet	+30 feet	6 hours
Lantern, bullseye	60 foot cone	+60 feet	6 hours
Lantern, hooded Lowered Hood	30 feet -	+30 feet + 5 feet	6 hours -
Torch	20 feet	+20 feet	1 hour
Magic Sources
Continual Flame	20 feet	+20 feet	-
Dancing Lights	-	10 feet	1 minute
Faerie Fire	-	10 feet	1 minute
Flame Blade	10 feet	+ 10 feet	10 minutes
Flaming Sphere	20 feet	+20 feet	1 minute
Holy Aura	-	5 feet	1 minute
Light	20 feet	+20 feet	1 hour
Moonbeam	-	5 ft cyl	1 minute
Prismatic Wall	100 feet	+100 feet	10 minutes
Wall of Fire	60 feet	+60 feet	1 minute

Trap Save DCs and Attack Bonuses
Trap Danger	Save DC	Attack Bonus
Setback	10-11	+3 to +5
Dangerous	12-15	+6 to +8
Deadly	16-20	+9 to +12

Damage Severity and Level
Character Level	Setback	Dangerous	Deadly
1st-4th	1d10	2d10	4d10
5th-10th	2d10	4d10	10d10
11th-16th	4dl0	10d10	18d10
17th-20th	10d10	18d10	24d10

Targets in Area of Effect
Area	Number of Targets
Cone	Size / 10 (round up)
Cube or Square	Size / 5 (round up)
Cylinder	Radius / 5 (round up)
Line	Length / 30 (round up)
Sphere or Circle	Radius / 5 (round up)

Improvising Damage
Damage	Example
1d10	Burned by coals, hit by a falling bookcase, pricked by a poison needle
2d10	Being struck by lightning, stumbling into a fire pit
4d10	Hit by falling rubble in a collapsing tunnel, stumbling into a vat of acid
10d10	Crushed by compacting walls, hit by whirling steel blades, wading through a lava stream
18d10	Being submerged in lava, being hit by a crashing flying fortress
24d10	Tumbling into a vortex of fire on the Elemental Plane of Fire, being crushed in the jaws of a godlike creature or a moon-sized monster

Object Armor Class
Substance	AC
Cloth	11
Paper	11
Rope	11
Crystal	13
Glass	13
Ice	13
Wood	15
Bone	15
Stone	17
Iron	19
Steel	19
Mithril	21
Adamantine	23

Object Hit Points
Size	Weak	Tough
TINY Bottle, Lock	1d4	2d4
SMALL Chest, Chain	1d6	3d6
MEDIUM Barrel, Chandelier	1d8	4d8
LARGE Cart, Window	1d10	5d10
HUGE+ Wagon, Hut	DM's Discretion

Resting

Short Rest:

A period of downtime lasting at least one hour, during which time you can do nothing more strenuous than eating, drinking, reading, or tending to wounds.
You regain the use of abilities, features, and resources that are refreshed by taking a Short Rest.
You are allowed to expend one of your accumulated Hit Die by rolling a die of the corresponding type. You regain hit points equal to the rolled value + your Constitution modifier. Afterwards, you may choose to spend another Hit Die.

Full Text: A short rest is a period of downtime, at least 1 hour long, during which a character does nothing more strenuous that eating, drinking, reading, and tending to wounds. A character can spend one or more Hit Dice at the end of a short rest, up to the character's maximum number of Hit Dice, which is equal to the character's level. For each Hit Dice spent in this way, the player rolls the die and adds the character's Constitution modifier to it. The character regains hit points equal to the total. The player can decide to spend an additional Hit Die after each roll. A character regains some spent Hit Dice upon finishing a long rest, as explained below.

Long Rest:

A period of extended downtime lasting at least eight hours, during which time you must either sleep or perform only light activities such as talking, eating, or standing watch. These activities can occupy no more than 2 hours of your Long Rest. Performing more than an hour of strenuous activity such as walking or fighting will also interrupt your Long Rest. You may only benefit from one Long Rest in a 24-hour period and you must begin the rest with at least one hit point.
You regain the use of abilities, features, and resources that are refreshed by a long rest
You regain all of your lost hit points unless otherwise indicated.
You regain a number of Hit Die equal to up half of your total possible Hit Die.

Full Text: A long rest is a period of extended downtime, at least 8 hours long, during which a character sleeps or performs light activity: reading, talking, eating or standing watch for no more than 2 hours. If the rest in interrupted by a period of strenuous activity - at least 1 hour of waking, fighting, casting spells, or similar adventuring activity - the characters must begin the rest again to gain any benefit from it. At the end of a long rest, a character regains all lost hit points. The character also regains spent Hit Dice, up to a number of dice equal to half of the character's total number of them. For example, if a character has eight Hit Dice, he or she can regain four spent Hit Dice upon finishing a long rest. A character can't benefit from more than one long rest in a 24-hour period, and a character must have at least 1 hit point at the start of the rest to gain its benefits.

Weather

Weather Chart

d20	Temperature
1-14	Normal for the season
15-17	1d4 x 10 degrees Fahrenheit colder than normal
18-20	1d4 x 10 degrees Fahrenheit hotter than normal

d20	Wind
1-12	None
13-17	Light
18-20	Strong

d20	Precipitation
1-12	None
13-17	Light rain or light snowfall
18-20	Heavy rain or heavy snowfall

Languages

Standard Languages

Language	Typical Speakers	Script
Common	Humans	Common
Dwarvish	Dwarves	Dwarvish
Elvish	Elves	Elvish
Giant	Ogres, giants	Dwarvish
Gnomish	Gnomes	Dwarvish
Goblin	Goblinoids	Dwarvish
Halfling	Halflings	Common
Orc	Orcs	Dwarvish

Exotic Languages

Language	Typical Speakers	Script
Abyssal	Demons	Infernal
Celestial	Celestials	Celestial
Draconic	Dragons, dragonborn	Draconic
Deep Speech	Mind Flayers, Beholders	—
Infernal	Devils	Infernal
Primordial	Elementals	Dwarvish
Sylvan	Fey creatures	Elvish
Undercommon	Underdark traders	Elvish

Random Tables

Quick Find

d12	Find
1	Artwork
2	Body
3	Food or drink
4	Jewelry
5	Key
6	Letter
7	Magic herbs
8	Map
9	Monster parts
10	Secret message
11	Signet or insignia
12	Tome

Something Happened

d20	Event
1	A door opens
2	A fire starts
3	A meteor shoots across the sky
4	A monster appears
5	A screech pierces the air
6	A storm begins
7	A strange star appears in the sky
8	A strong gust of wind blows through
9	A tremor shakes the ground
10	Someone experiences déjà vu
11	Someone gets angry
12	Someone glimpses the future
13	Someone has a sense of foreboding
14	Someone has to go to the bathroom
15	Something spills or falls to the ground
16	Something isn't where it's supposed to be
17	The lights go out
18	The sun comes out
19	There's a foul smell in the air
20	Unexplained magic occurs

Dungeon Hazards

d20	Hazard
1-3	Brown Mold
4-8	Green slime
9-10	Shrieker
11-15	Spiderwebs
16-17	Violet fungus
18-20	Yellow mold

Dungeon Obstacles

d20	Obstacle
1	Antilife aura with a radius of 1d10 x 10 ft.; while in the aura, living creatures can't regain hit points
2	Battering winds reduce speed by half, impose disadvantage on ranged attack rolls
3	Blade barrier blocks passage
4-8	Cave-in
9-12	Chasm 1d4 x 10 ft. wide and 2d6 x 10 ft. deep, possibly connected to other levels of the dungeon
13-14	Flooding leaves 2d10 ft. of water in the area; create nearby upward-sloping passages, raised floors, or rising stairs to contain the water
15	Lava flows through the area (50% chance of a stone bridge crossing it)
16	Overgrown mushrooms block progress and most be hacked down (25% chance of a mold or fungus dungeon hazard hidden among them)
18	Poisonous gas (deals 1d6 poison damage per minute of exposure)
18	Reverse gravity effect causes creatures to fall towards the ceiling
19	Wall of fire blocks passage
20	Wall of force blocks passage

Trap Trigger

d6	Trigger
1	Stepped on (floor, stairs)
2	Moved through (doorway, hallway)
3	Touched (doorknob, statue)
4	Opened (door, treasure chest)
5	Looked at (mural, arcane symbol)
6	Moved

Trap Severity

d6	Severity
1-2	Setback
3-5	Dangerous
6	Deadly

Use these charts to determine attack bonus, save DC, and damage for the trap.

Trap Effect

d100	Effect
01-04	Magic missiles shoot from a statue or object
05-07	Collapsing staircase creates a ramp that deposits characters into a pit at its lower end`
08-10	Ceiling block falls, or entire ceiling collapses
11-12	Ceiling lowers slowly into locked room
13-14	Chute opens in floor
15-16	Clanging noise attracts nearby monsters
17-19	Touching an object triggers a disintegrate spell
20-23	Door or other object is coated with contact poison
24-27	Fire shoots out from wall, floor, or object
28-30	Touching an object triggers a flesh to stone spell
31-33	Floor collapses or is an illusion
34-36	Vent releases gas: blinding, acidic, obscuring, paralyzing, poisonous, or sleep-inducing
37-39	Floor tiles are electrified
40-43	Glyph of warding
44-46	Huge wheeled statue rolls down corridor
47-49	Lightning bolt shoots from wall or object
50-52	Locked room floods with water or acid
53-56	Darts shoot out of an opened chest
57-59	A weapon, suit of armor, or rug animates and attacks when touched (see "Animated objects" in the Monster Manual)
60-62	Pendulum, either bladed or weighted as a maul, swings across the room or hall
63-67	Hidden pit opens beneath characters (25% chance that a black pudding or gelatinous cube fills the bottom of the pit)
68-70	Hidden pit floods with acid or fire
71-73	Locking pit floods with water
74-77	Scything blade emerges from wall or object
78-81	Spears (possibly poisoned) spring out
82-84	Brittle stairs collapse over spikes
85-88	Thunderwave knocks characters into a pit or spikes
89-91	Steel or stone jaws restrain a character
92-94	Stone block smashes across hallway
95-97	Symbol
98-00	Walls slide together

Trick Objects

d20	Object
1	Book
2	Brain preserved in a jar
3	Burning fire
4	Cracked gem
5	Door
6	Fresco
7	Furniture
8	Glass sculpture
9	Mushroom field
10	Painting
11	Plant or tree
12	Pool of water
13	Runes engraved on wall or floor
14	Skull
15	Sphere of magical energy
16	Statue
17	Stone Obelisk
18	Suit of armor
19	Tapestry or Rug
20	Target Dummy

d100	Trick Effect
01-06	Ages the first person to touch the object
04-06	The touched object animates, or it animates other objects nearby
07-10	Asks three skill-testing questions (if all three are answered correctly a reward appears)
11-13	Bestows resistances or vulnerability
14-16	Changes a character's alignment, personality, size, appearance, or sex when touched
17-19	Changes one substance into another, such as gold to lead or metal to brittle crystal
20-22	Creates a force field
23-26	Creates an illusion
27-29	Suppresses magic items for a time
30-32	Enlarges or reduces characters
33-35	>Magic mouth speaks a riddle
36-38	Confusion (targets all creatures within 10 ft.)
39-41	Gives directions (true or false)
42-44	Grants a wish
45-47	Flies about to avoid being touched
48-50	Casts geas on the characters
51-53	Increases, reduces, negates, or reverses gravity
54-56	Induces greed
57-59	Contains an imprisoned creature
60-62	Locks or unlocks exits
63-65	Offers a game of chance, with the promise of a reward or valuable information
66-68	Helps or harms certain types of creatures
69-71	Casts polymorph on the characters (lasts 1 hour)
72-75	Presents a puzzle or riddle
76-78	Prevents movement
79-81	Releases coins, false coins, gems, false gems, a magic item, or a map
82-84	Releases, summons, or turns into a monster
85-87	Casts suggestion on the characters
88-90	Wails loudly when touched
91-93	Talks (normal speech, nonsense, poetry and rhymes, singing, spellcasting, or screaming)
94-97	Teleports characters to another place
98-00	Swaps two or more character's minds

Madness Tables

Short-Term Madness

d100	Effect (lasts 1d10 minutes)¹
01-20	The character retreats into his or her mind and becomes paralyzed.
21-30	The character becomes incapacitated and spends the duration screaming, laughing, or weeping.
31-40	The character becomes frightened and must use his or her action and movement each round to flee from the source of the fear.
41-50	The character begins babbling and is incapable of normal speech or spellcasting.
51-60	The character must use his or her action each round to attack the nearest creature.
61-70	The character experiences vivid hallucinations and has disadvantage on ability checks.
71-75	The character does whatever anyone tells him or her to do that isn't obviously self-destructive.
76-80	The character experiences an overpowering urge to eat something strange such as dirt, slime, or offal.
81-90	The character is stunned
91-100	The character falls unconscious

¹ A calm emotions spell can supress the effects of madness, while a lesser restoration spell can rid a character of long-term madness. Depending on the source of the madness, remove curse or dispel evil might also prove effective.