You can move a distance up to your Speed on your turn. With that in mind, how you choose to move and how much movement you use are all up to you.

Size and Space

Creatures and objects come in all different shapes and sizes. To determine the amount of space one can effectively command, Table: Size Categories approximates a standard for Turn-Based Action.

The 5-foot square that a Medium orc commands cannot be passed through by other Medium creatures unless the orc allows them to. Likewise, the space determines the limit to the number of creatures that can surround it; the orc can be surrounded by a maximum of 8 Medium creatures, or 4 Large creatures.

Squeezing

A creature usually has the option to squeeze through a space one size smaller than its own. A Large ogre can explore a 5-foot wide tunnel or narrow crevice with her Small goblin friend by squeezing, although it'll be a little difficult. 

While you are squeezing:

• Your movement speed is halved.
• You have disadvantage on ability checks, attack rolls, and Dexterity saving throws .
• Ability checks and attack rolls made against you have advantage .

Movement in Turn-Based Action

Your Speed centers around moving across the ground by running, walking, rolling, slithering, and so on. Any natural or magical means can provide you with additional speeds based on other forms of movement.

Climbing and Swimming. You can use your base Speed to perform these tasks, but you must spend 1 extra foot for every foot you do so. A swim or climb speed allows you to move through these environments at no additional cost.

Gliding, Hovering, and Burrowing. You must have the appropriate movement speed to perform these tasks.

Flying. Not only do you need to have a flying speed to fly, you may fall out of the sky when you are knocked prone or have your Speed reduced to 0.

When switching between different movement speeds, you subtract the distance you've already moved during your turn from the new speed. If the remainder is 0 or less, you cannot use the new speed this turn.

The way you break up your movement between speeds is up to you. If you have two attacks and a Speed of 30 feet, you can move 15 feet, perform an attack, move another 15 feet, and then attack a second time. If you have more than one movement speed, like a swim speed of 30 feet, you can run 10 feet, swim across a pool for 10 feet, and then run another 10 feet on the other side.

Mounted Combat

A creature can ride on top of another creature at least one size larger than its own, provided the bigger creature can support its weight. Mounting or dismounting a creature costs half your movement and can be performed once per turn. 

While you are mounted on a creature:

• You have half cover (+2 to AC, Dexterity saving throws , and ability checks made to hide) against melee attacks.
• You have advantage on ability checks to leap off the creature you're riding.
• If you are knocked prone , you make a DC 10 Dexterity saving throw or fall prone in a space adjacent to the creature you're riding.
• If the creature you're riding is knocked prone, you can use your reaction to dismount and land on your feet. Otherwise, you also fall prone.

While you are being ridden by another creature:

• You have advantage on ability checks to throw the creature riding you.

If you're riding another creature that you have control of, you use its Speed instead of your own, and you and your mount share movement on your turn. Remember that mounting or dismounting costs half your Speed when choosing to move after you’ve jumped onto or off the creature.

A mounted creature under your control can take the Dash, Disengage, or Dodge action during your movement on your turn. Alternatively, you can use a bonus action to command the creature to make an ability check or take the Attack action (this does not include Multiattack). You can read more about these actions later in this chapter.

Being Prone

Falling down on the ground is often a consequence of action, but it can also be an effective strategy in the heat of the moment while bolts of lightning whiz overhead. You can drop prone without using any movement. You can also drop prone as a reaction to being targeted by a ranged attack you can see.

While you are prone:

• Your only movement option is to crawl (every 1 foot of movement while crawling costs 1 extra foot) until you stand up.
• Standing up requires half your movement.
• You have disadvantage on melee attack rolls.
• An attack roll against you is made with advantage if the attacker is within 5 feet. Otherwise, the attack roll is made with disadvantage.

Tactical Positioning

Position in combat can give you or your allies the upper hand during Turn-Based Action.

Attacking From Above

If you are at least 5 feet above your target and you aren't grappled or restrained , you gain an expertise die on melee attack rolls made against it. 

Back-To-Back

When you are adjacent to an ally, you can use a bonus action to stand back-to-back. While back-to-back with an ally it is harder to be caught off guard, and you cannot be flanked. As long as neither you nor your ally move, your passive Perception is increased by 2 until either the start of your next turn or when one of you moves.

Dragging An Ally

While adjacent to a willing ally, you can use your reaction to grab them by the hand and pull them along with your movement even if they've already expended all of theirs. While doing so, every foot of movement costs you an additional 2 feet of movement, and the ally cannot use their reaction. This movement provokes opportunity attacks as normal.

Flanking

When you and an ally are on direct opposite sides of a target, you gain an expertise die on your actions against that target. You and your ally cannot flank for one another if either of you are incapacitated .

If you are not using a grid for combat, flanking instead occurs when three or more creatures are attacking the same creature in melee.

Pulling From Below

If you are at least 5 feet below your target, your target is your size or smaller, and you aren't grappled or restrained , you gain an expertise die on Strength checks and saving throws made against it.

Hidden Attacker

When you are hidden from a target, you gain advantage on your first attack roll against it. After your first attack roll, unless you are invisible or your target is otherwise unable to see you, you are no longer hidden.

On Your Turn

When it is your turn, you can move a distance up to your Speed and take your actions. You can declare your intent for your turn in any order, breaking up your movement between actions or using your bonus action first. You can also choose to do absolutely nothing.

Within a single round, you can take an action, a bonus action, and any free actions during your turn, and one reaction at any time. The rules for actions and movement are found in the Actions in Combat and Movement and Position sections of this chapter, respectively.

Off Your Turn

You're still an active participant in Turn-Based Action even when it's not your turn! You have a number of responsibilities to keep track of within an encounter in between taking actions.

1. Plan your actions so you're ready when your turn comes. Creatures who carry long lists of spells especially have a lot of options to manage, and you might not want to spend your precious 6 seconds flipping through a book.

2. Pay attention to the encounter beyond events that involve you. The priorities of you and your allies can change in the blink of an eye, and the actions you were planning can become inappropriate for the task.

3. Be prepared to use your reaction. Reactions have specific conditions that can occur at any time and you don't want to let a golden opportunity escape your grasp.

End of Round

Once all participants have taken their turn, the encounter returns to the start of a new round. The loop persists until the action concludes, or the granularity of Turn-Based Action is no longer needed.

The raging storm howls and a bolt of lightning splits the ground in front of the adventurers. Souls lost to the sea manifest amid the fervor of the fishing competition for another chance at the perfect catch. The battlefield itself can be as active a participant in Turn-Based Action as the characters are, and its actions can have serious consequences for everyone involved.

Some world bonuses and penalties have an effect that activates within the initiative count. These world actions occur at the start of each round before any participants act. The Narrator determines if any participants are within the range of these effects and adjudicates the action accordingly.

World Bonuses, Penalties, and Cover

The action hardly happens in a featureless void. Craggy roads, chandeliers of suspect quality, and figures reaching out from the mists for fresh blood can all greatly shape the way you move through the world.

World benefits and world penalties are objects, obstacles, and field conditions in the immediate area. They might provide you with bonuses, or can slow you down and provide another source of danger.

Difficult Terrain

One of the most common forms of world penalties is difficult terrain. Anything from dense bramble, precarious steps, or tenacious mud can slow you down from your normal movement speed.

Every foot of movement you take within difficult terrain costs 1 extra foot. Multiple hazards that would cause difficult terrain in a space do not stack. However, additional conditions that increase the cost of movement (such as crawling while prone ) stack with difficult terrain.

Cover

A common world benefit presents cover for participants that stumble on it. Larger obstacles such as trees and stone walls can help to keep creatures out of sight and out of harm's way.

Cover provides you with protection from attacks and effects that originate on the other side of it. There are three degrees of cover: half, three-quarters, and total cover. If you are behind multiple sources of cover, you only gain the benefits from the most protective source of cover.

Half cover is provided by obstacles that block at least half of your body, such as a tree trunk or another creature. Half cover provides you with a +2 bonus to AC, Dexterity saving throws , and ability checks made to hide.

Three-quarters cover obscures three-quarters of your body, like an arrow slit or a castle wall. It provides you with a +5 bonus to AC, Dexterity saving throws , and ability checks made to hide.

Total cover keeps you completely concealed from the other side. You cannot be targeted directly by attacks, spells, or ability checks, although spells that target an area of effect and checks to search the area might still reach you.

World Actions

Environments are often dynamic spaces with moving parts other than their inhabitants. Within Turn-Based Action, the world gets its own turn to enact these moving parts in the form of a world action.

World actions have a variety of specific effects depending on the environment. A bolt of lightning might strike near a single participant. The fumes from the swamp could thicken and choke the people in it. New participants might even emerge from the landscape and jump right into the action!

After the environment uses a world action with a recharge, the Narrator rolls 1d6. On a result equal to or greater than the listed number, the environment regains its world action. Otherwise at the start of each round the Narrator repeats the roll until the environment regains the world action.

Example Environments

If a particular bonus, penalty, or action doesn't make sense for where the participants are located, the Narrator can reskin a different environment's effects or forgo using them altogether for a Turn-Based Action encounter. That said, an unexpected effect can prompt creativity, challenge, and intrigue in the game.

CAVERNOUS

• Echo. Sound travels twice as far, and any effect which causes thunder damage does 1 extra point of damage per die rolled.
• Loose Foundation. Area hazard that can cause the entire section of cave to collapse within 2 rounds of being disturbed by any explosive effect or significant impact. Participants still in the area are grappled and start to suffocate (escape DC 12).
• Stalactites. Obstacles that can be knocked down by ranged attacks that deal any damage (AC 12). The creature beneath a stalactite makes a DC 12 Dexterity saving throw or takes 2d6 piercing damage.
• Stalagmites. Obstacles that each provide half cover .

FIERY

• Burning Surface. Touching an unattended object or a surface for the first time on a participant’s turn causes them to take 1d6 fire damage. 
• Floating Ash. A participant that ends their turn in this area hazard makes a DC 10 Constitution saving throw or is blinded until the start of their next turn.

World Actions

• Flame Burst (Recharge 4–6). A single participant makes a DC 12 Dexterity saving throw or they take 1d12 fire damage.
• Sweltering Heat. All participants make a DC 10 Constitution saving throw or suffer one level of fatigue .

FORESTED

• Brush. Obstacle provides half cover while a participant is prone behind it.
• Trees (Fallen or Standing). Obstacle provides half cover .
• Fallen Leaves. Area hazard that may conceal potholes, traps, and other hazards. Participants can perceive what’s under the leaves by making a DC 12 Wisdom (Perception) check.

World Actions

• Distressed Animal Cacophony (Recharge 4–6). All participants can only hear sounds within 10 feet of them (except for loud, explosive noises).

FRIGID

• Frostbitten Surface. Touching an unattended object or a surface for the first time on a participant’s turn causes them to take 1d6 cold damage. This effect is nullified if they have resistance to cold damage or the participant’s skin isn’t exposed to the surface.
• Icy Patch. When a participant starts moving in a single direction through this area hazard, movement in another direction is considered difficult terrain until the start of their next turn.
• Snow. The area is lightly obscured .

World Actions

• Cold Chill (Recharge 4–6). All participants make a DC 15 Constitution saving throw or take 2d6 cold damage. This damage is reduced to 1d6 if they are wearing cold weather gear.

FURNISHED

• Chandelier. Obstacle can be swung from with a DC 12 Dexterity (Acrobatics) check, or knocked down dealing 2d6 bludgeoning damage to any creatures underneath (each makes a DC 12 Dexterity saving throw to negate the damage).
• Clutter. Area hazard that counts as difficult terrain . If a participant uses the Dash action to move through the area, they make a DC 10 Dexterity saving throw or fall prone .
• Mirror. A participant using this Medium-sized object as cover can use their reaction to reflect a 1st-level spell or cantrip targeting them, turning it back onto the spellcaster by succeeding on a Dexterity check opposed by a spellcasting ability check (on a failure, the spell hits a randomly determined unoccupied square). The mirror then breaks.
• Tables. Obstacles that can be pushed over as an action to provide half cover.

HAZY

• Blanketed Ground. Area hazard that may conceal potholes, traps, and other hazards. Participants can perceive what’s under the fog by making a DC 12 Wisdom (Perception) check.
• Thick Fog. The area is heavily obscured .

World Actions

• Shadow Puppet (Recharge 6). A shadow that looks identical to a random participant in the haze manifests and is hostile to everyone (initiative 20). The shadow can see through the fog clearly.
• Twisting Haze. All participants in the haze move into randomly determined unoccupied spaces within 5 feet.

ROCKY

• Boulder. Obstacle can be dislodged and made to roll with a DC 15 Strength (Athletics) check, dealing 2d10 bludgeoning damage to any creatures in its way (each makes a DC 12 Dexterity saving throw to negate the damage).
• Loose Rocks. Object can be used for a thrown weapon attack (1d4 bludgeoning, range 15/30 feet).
• Uneven Footing. Area hazard that counts as difficult terrain .

World Actions

• Falling Rocks (Recharge 5–6). Participants near a treacherous cliffside make a DC 15 Dexterity saving throw or take 2d6 bludgeoning damage.

STORMY

• Heavy Precipitation. The area counts as difficult terrain .
• Loud Winds. All participants can only hear sounds within 15 feet of them (except for loud, explosive noises).

World Actions

• Forceful Gale. A single participant makes a DC 12 Strength saving throw or they are pushed 15 feet in one direction. This movement does not provoke opportunity attacks .
• Lightning Strike (Recharge 5–6). A single participant makes a DC 10 Dexterity saving throw or they take 4d6 lightning damage. They cannot be targeted by this action again until Turn-Based Action ends.

SWAMPY

• Thick Trudge. Area hazard that counts as difficult terrain.
• Tenacious Mud. When a participant ends their turn in this area hazard, they make a DC 12 Strength saving throw or are restrained until the end of their next turn. They can use their action to break free of this effect.

World Actions

• Swamp Gas. Participants in mud make a DC 10 Constitution saving throw or are poisoned until the end of their next turn.
• Leeches (Recharge 6). A swarm of insects (leeches) rises out of the swamp to attack any creature in the marsh.

The initiative step sets the order of everyone's turn throughout the encounter. Each participant makes an ability check to determine their place in the initiative count, from the highest check total to the lowest. This ability check is typically Dexterity. The Narrator might determine that one or more participants should instead roll a different ability check, potentially utilizing a relevant skill or tool (see Table: Types of Initiative). In the event of a tie, the tied participants each roll a d20 to determine the order amongst themselves (the highest roll goes first.)

If any creatures have already made an ability check during the surprise step, they use that existing score for initiative.

The party lurks in the shadows of the cult’s ritual, looking for the right moment to cut it short. A sneaky athlete sprints ahead before the start of the race and the other racers catch on. A noble suddenly draws her sword and lunges at the king.

If some participants are unaware of others due to successful attempts to be stealthy, they begin the encounter surprised. The Narrator calls for appropriate ability checks to determine whether participants are aware of each other. Surprised creatures are unable to move or take an action on their first turn, and are unable to use a reaction until after their first turn.

Sometimes all participants are aware of each other at the beginning of an encounter, but one side takes an action or launches an attack while others' guards are down. In this case, no one is surprised, but the Narrator may allow the instigating creature or party to roll initiative with advantage.

If nobody is trying to be sneaky, combat begins normally with initiative .

All engagements using Turn-Based Action consist of two phases: set-up and initiative rounds. The set-up phase establishes the status and order of the participants and the amount of time each round takes in the game world, and initiative rounds are where the participants take their turns round after round until one side is victorious.

Set-up

1. Set the Scene. The Narrator decides where everyone is located, the appropriate amount of time for each round, and any important condition of the engagement. 
2. Surprise. If any characters intend to act before all participants are aware of the encounter, the Narrator calls for ability checks to determine if any combatants are surprised.
3. Roll Initiative. The remaining participants roll initiative and determine the turn order.

Initiative Rounds

1. World Actions. If the environment features any world bonuses or penalties with an active element, it occurs at the start of a round before the participants take their turns.
2. On Your Turn. The active character moves and uses their available actions.
3. Off Your Turn. The inactive characters plan their next turn and prepare to react to the active character's actions.
4. End of Round. When everyone has taken their turn, the initiative round repeats at step 1 until the encounter has concluded.

On Your Turn

When it is your turn, you can move a distance up to your Speed and take your actions. You can declare your intent for your turn in any order, breaking up your movement between actions or using your bonus action first. You can also choose to do absolutely nothing.

Within a single round, you can take an action, a bonus action, and any free actions (like communicating with allies, dismissing the effect of a thaumaturgy cantrip you have already cast, or interacting with an object) during your turn, and one reaction at any time. The rules for actions and movement are found in the Actions in Combat and Movement and Position sections of this chapter, respectively.

Off Your Turn

You're still an active participant in Turn-Based Action even when it's not your turn! You have a number of responsibilities to keep track of within an encounter in between taking actions.

1. Plan your actions so you're ready when your turn comes. Creatures who carry long lists of spells especially have a lot of options to manage, and you might not want to spend your precious 6 seconds flipping through a book.
2. Pay attention to the encounter beyond events that involve you. The priorities of you and your allies can change in the blink of an eye, and the actions you were planning can become inappropriate for the task.
3. Be prepared to use your reaction. Reactions have specific conditions that can occur at any time and you don't want to let a golden opportunity escape your grasp.

End of Round

Once all participants have taken their turn, the encounter returns to the start of a new round. The loop persists until the action concludes, or the granularity of Turn-Based Action is no longer needed.

Turn-Based Action provides a structure for all characters and creatures in the immediate area to engage with one another at the same time whether for combat or other dangerous scenarios. These rules refer to "you" and specify either the player or the character(s) you control. The Narrator controls all the nonplayer characters and creatures in Turn-Based Action while each other player controls their adventurer.

The most common use for Turn-Based Action is combat.

When to Use Turn-Based Action

Turn-Based Action can be called when a hostile action is taken, the characters enter a precarious location or situation, or at the start of a competition. Whenever methodical actions are necessary from multiple characters at the same time, this system presents the scene in a way that everyone gets the spotlight.

Setting the Scene

The Narrator establishes the conditions of any Turn-Based Action encounter. This includes the known participants and their positions, any active elements and known world bonuses or penalties in the environment, and the length of each round.

A round encompasses the semi-simultaneous actions of the participants within a period of game world time. For combat, one round is usually 6 seconds. In other cases a round might take 10 seconds, 1 minute, or 10 minutes as deemed appropriate by the Narrator.