One of the staples of role-playing games is combat. Nothing quite raises the drama and tension of a story like a literal life or death struggle with your opponents. Combat is up close and personal, chaotic, and usually quick. To resolve a combat encounter in an orderly and fair manner while still maintaining the drama, we use combat rounds to break down all allowable actions and the order they occur. Each round represents just a few seconds of time, generally enough time for a quick spell casting, firing a bow, a quick attack and parry with a sword, or drinking a potion. The types of rounds, how they are resolved, and what actions are allowed are listed below. Once a round is complete, if there are still combatants alive to fight, you start at the top of a normal round and go again until one side is dead or has fled the battlefield.
Combat can be started when both parties see or hear each other or when one party catches another by surprise. Based on the situation, combat will begin either with a surprise round or a normal round. For example, the party is taking their time stealthily moving through the forest and hears a group of ogres up ahead. The ogres are in the middle of an argument, and they do not hear the party approaching. When the party attacks, the GM would initiate a surprise round to start that encounter. Conversely, if the party is walking down the street singing and laughing and their hated enemy is running down the street towards them, neither party is surprised by the others presence and combat would begin with a normal round.
Surprise Round
An opposed roll is taken by one member on each side, if attackers roll higher, they gain surprise, if they roll 5 over the other side, they gain full surprise. The opposed roll uses different bonuses depending on what side you are on, attacker or defender.
Depending on the result of the opposed roll, one party may attain surprise or full surprise over the other party, and they gain the following effects for that round:
Normal Round
Everyone declares what they are going to do within X seconds or minutes depending on the complexity of the situation and the size of the group as determined by the GM. The GM can give you a set time to make your plans each round or they can let you know you are taking too long as necessary. Each round is only a few seconds long so there is not time to make overly complex and coordinated plans and time is of the essence.
Initiative is rolled (Outlined in the Initiative section below).
Each group takes their actions in order. GM and players work together to narrate what happens (i.e., the GM decides who hits first and applies damage, players describe killing blows or what special effect or condition to bestow).
Additional Factors in Combat
Opposition rolls are used for things like shutting the door before the enemy gets through and the higher roll wins.
Timer dice: roll the die determined by the GM and that is the number of rounds until something happens like the ceiling collapses, cliff falls away, barrels explode, etc.
Declared Actions
Before Initiative is rolled for the round, each player declares their action and the GM declares the actions of each creature. Once the round begins, the actions declared cannot be changed. Since a round only represents a few seconds in time it would be nearly impossible for someone to start swinging at one creature and then change their mind and run over to another creature and attack it instead.
Players can switch the order of who takes their actions each round during their group initiative, so the group can use the declaration phase to come up with some interesting tactics.
For example: The players declare their actions for the round and determine that Larry is going to cast a Sleep spell on the goblin pack, Jenny is going to attack the nearest goblin standing after Larry casts his spell, and Bruno is going to standby to counter spell anything the enemy wizard might throw at them.
The GM can allow a change in declared action if the circumstances warrant it (e.g., Carl declared that he was going to shoot an arrow at the ogre across the room, but before his action that ogre is killed. There is an orc right next to the dead ogre so the GM determines that Carl can easily shift his target the tiny amount necessary to fire on the orc instead. However, if Carl were charging at the ogre with a spear and the ogre was pushed out of the way before Carl got to it, the GM could say that Carl just keeps running past the ogre and cannot change his direction in time).
Initiative
Once everyone has made their declarations for the round, one player in the group rolls a d10 for group initiative and the GM rolls a d10 for initiative for each group of creatures in the combat. In most cases, this will be one big group, but the GM could have all the normal creatures as one group and a boss monster as another group as an example of multiple groups. The highest roll goes first and so on until each group has taken their actions.
Initiative is rolled at the start of each round so initiative order can change from round to round to represent the chaos and changing momentum of battle. Note, this can result in one group going last in a round and then first in the next round and getting two sets of actions before the other group gets a response, but that is just the chaos of combat.
To Hit Rolls
Each player and creature involved in combat rolls a to hit roll against the target or spell DC to determine if their attack succeeds. A to hit roll is made with a d20 + the bonus of the applicable skill (i.e., a melee weapon attack is d20+melee skill bonus, a spell casting is d20+casting skill bonus, etc.).
The GM can determine that a player or creature has Advantage or Disadvantage or Cinematic Advantage on a to hit roll and that roll is made with two or three d20's as per the Advantage and Disadvantage rules in the Dice section of the rules. Examples of situations granting Advantage would be several players attacking the same creature from different sides or flanking the creature, attacking a surprised creature, attacking from the high ground. Examples of situations granting Disadvantage would be attacking while on a slippery or unstable surface like a boat deck in a storm, attacking a creature several times smaller than you (trying to knock a pixie out of the air), or acting while Exhausted.
Long Range Attacks
None of the weapons or creatures in the game are given maximum ranges for their attacks, but the GM can determine that a specific attack is outside the normal accurate range of a given attack and assign Disadvantage to the to hit roll (e.g., Jen is an accomplished archer and attempts to fire an arrow at a troll that is on the other side of a large chasm. The GM determines it is an extreme shot with a bow and Jen is given Disadvantage for her to hit roll for the shot).
Called Shots
Aiming for a specific location on a target, called shot, or taking special actions against an unwilling target gain Disadvantage on the to hit roll (e.g., Linda attempts to shoot the wand out of a wizard’s hand. She makes her standard Ranged attack roll with Disadvantage on the roll).
Cover
Hiding behind cover provides Disadvantage when attacking a creature under cover. A creature under cover also takes half damage from any area effect attacks or conditions coming from the other side of their cover. Direct attacks that succeed in hitting a creature under cover provide full damage.
Sneak Attack
If an attacker successfully used the Stealth skill in the previous round and attacks an unsuspecting target, they gain Advantage to hit.
Critical Failure
A roll of 1 on a d20 for to hit is a critical failure and always misses even if bonuses would normally allow the roll to succeed. What happens on a critical failure is determined by the GM or the GM and players together as appropriate. Sample critical failures are:
Critical Success
A roll of 20 on a d20 for to hit is a critical success and always hits even if the roll would not have succeeded with bonuses applied. When using a melee or ranged weapon critical successes are considered critical hits and the weapon damage rolled for that attack is doubled. For spells, the effect of a critical success is listed in the spell description. In some cases, a GM and the players may decide to apply a custom effect to the critical success instead of doubling the damage. The custom effects take the place of doubling damage and are not to be stacked with the double damage effect. Sample critical hits are:
Every weapon or attack rolls an appropriate die for damage. In most cases the die used to determine the damage a weapon, spell, trap, or other standard attack causes is listed in the item/spell/trap description in the Setting Pack. A critical hit doubles the amount of damage rolled (i.e., Tammy rolls a 20 for to hit on a sword strike and gets a critical hit. She rolls a d6 for damage and rolls a 5. She doubles the damage to 10 for the critical hit).
Weapon Damage Optional Rule
In most cases, the standard damage rules will be more than enough for many groups. However, if you are finding the options for damage dice that can be assigned to attacks to be a bit limiting, you can use this set of optional rules in your setting.
Damage Reduction (DR)
Armor and other effects have a DR rating. Before Damage is applied, it is reduced by the DR of the creature being hit (e.g., Bob is a warrior charging into battle wearing a maille shirt with a DR of 2. An ogre takes a swing at Bob and hits him. The Ogre rolls a d6 for damage and rolls a 5. DMG 5 minus DR 2 means that Bob only takes 3 points of damage from the hit). Some special weapons or some non-damage types of spells may disregard DR and will indicate that in their listing (e.g., The sleep spell is not affected by any armor you are wearing so the armor's DR is not applied to the sleep spells effects).
The amount of damage you take can affect your ability to keep fighting or successfully perform other actions. Listed below are the effects of reduced hit points due to damage:
Minions die on one hit. Regular monsters and bosses have a set amount of hit points.
Non-Damage Attacks
Most of the time the combatants are seeking to kill or wound their opponents enough to render them no longer a threat. However, there are times when you may wish to subdue, or incapacitate a foe so you can interact with them later. In these cases, you can make attacks on the target that are not intended to kill or maim them. These generally fall into three types of attacks.
During each round, a player may perform one attack and one move action. The other actions listed below will specify if they still allow for an attack or move or if they take up both of those actions when performed.