Unlike many other TTRPGs, combat in GURPS is processed in 1 second intervals. Each turn is a single second, a single action. There is no distinction between what kind of action takes up how much time on your turn, there are no free actions, bonus actions, or action economy. You get one action from a simple list of maneuvers.
Head over to the Maneuvers page for more detailed descriptions of the following maneuvers.
The order of combat is determined by each character's Basic Speed.
Order: Characters act from highest Basic Speed to lowest.
Ties: If Basic Speed is tied, the character with the higher DX (Dexterity) goes first. If still tied, the GM may use a die roll to decide.
Permanence: Once set at the start of combat, this order rarely changes.
On your turn, you must choose one maneuver to perform. Most maneuvers allow for a "Step" (usually 1 yard) of movement either before or after your main action. Common maneuvers include:
Aim: Add your weapons Accuracy to your next attack.
Attack: Make one attack and take a step.
Move: Move your full Basic Move distance.
Move and Attack: Move some distance and attack at a penalty.
All-Out Attack: Take a massive bonus to hit or damage, but you cannot defend until your next turn.
All-Out Defense: Choose two different defenses against one attack, or get a +2 bonus to one defense, but you cannot attack.
Ready: Prepare a weapon, pick up an item, or reload.
Concentrate: Take a mental action like casting a spell, manifesting an ability, or studying an opponent.
For a full list of maneuvers and their details go here: Maneuvers
Combat follows a simple three-step check for every strike:
Attack Roll: The attacker rolls 3d6. They must roll equal to or under their effective weapon skill to succeed.
Defense Roll: If the attack hits, the defender immediately chooses one Active Defense (Dodge, Parry, or Block). If the defender rolls equal to or under their defense score, the attack is negated.
Damage & Armor: If the defense fails, the attacker rolls for damage. Subtract the defender’s DR (Damage Resistance) from the total. Any remaining "penetrating damage" is then multiplied based on the damage type (e.g., x1.5 for cutting, x2 for impaling).
Damage is subtracted from HP (Hit Points).
Shock: If you take damage, you suffer a penalty to DX and IQ on your next turn (usually -1 per HP lost, max -4).
Major Wounds: Taking more than 1/2 your total HP in one hit can cause you to fall down or be stunned.
Zero HP: At 0 HP or less, you must roll against