Standard combat actions are technically listed in the Player’s Handbook, but for ease of reference, I’m adding them here. These actions can be used by anybody in combat.

• Movement in Combat:
  A character can move up to his movement rate x10 in feet during a combat round.
  He can move half this distance and still do a full melee attack. A character with the ‘Rapid Combatant’ fighting style can move at his full movement rate and still do a full melee attack.
  If firing a missile weapon or throwing a weapon, a character can move half this distance and fire at half their normal rate of fire. A character with the ‘Rapid Fire’ fighting style can move half this distance and still benefit form their full rate of fire.
  If a character moves and then attacks, he will be shunted to the end of the initiative order, to illustrate the time it takes to move. If multiple people are moving in one round, they will act in order of their initial initiative roll.
  A character can forgo all attacks and move their full movement rate. They are still allowed a free action either at the end or the beginning of their movement.
  A character can run at 2x their movement rate. They are not allowed any other actions beyond the movement, they suffer a -1 penalty to AC, and lose their Dexterity bonus to AC as well. If they run into a space where someone has readied a weapon to receive a charge, they will receive double damage from that weapon.
  Additionally, a character can make a short step and still benefit form their full attacks. This step can be no more than 5 feet, usually. This type of movement is relatively flexible and up to the DM’s discretion. It is meant to represent the fluidity of combat movement.

• Flanking and Rear attacks:
  If a character is able to position themselves for a flanking attack (attacking from the side, when the target’s attention is drawn away by another attacker), they receive a +1 bonus to hit.
  Attacking from the rear gives the character a +2 bonus to hit, and the target loses the benefit of their Dexterity and Shield bonuses to AC. Thieves that announce a Backstab attack, gain a +4 bonus to hit from the rear.

• Charge:
  A character can charge an opponent. A charge increases the character’s movement rate by 50% and enables the character to make an attack at the end of their movement. A charging character gains a +2 to their attack roll, mainly from momentum and the intimidation factor. Certain weapons (such as a lance) inflict double damage on a charge.
  Charging does reduce the character’s AC by 1 as it is a more reckless action. (They still retain their Dexterity bonus to AC contrary to what is written in the PHB)
  Charging also grants the opponent a -1 bonus to initiative, as it is an obvious attack.
  Certain weapons (such as most polearms) can be set to receive a charge and inflict double damage on a successful hit. Polearms usually have reach, and will inflict their damage before a charging strike can land.
  If a character moves and then attacks, as with a charge, he will be shunted to the end of the initiative order, to illustrate the time it takes to move. If multiple people are moving in one round, they will act in order of their initial initiative roll.

• Retreat:
  To get out of combat, characters can make a careful withdrawal, or simply flee.

Withdrawing: When making a withdrawal, a character carefully backs away from his opponent (who can choose to follow). The character moves up to 1/3 his normal movement rate. He cannot attack, cast spells, or perform any other action except this movement that round, as he is focusing on avoiding being hit.
If two characters are fighting a single opponent, the remaining character can block the advance of the opponent. This is a useful method for getting an injured ally out of combat.

Fleeing: To flee from combat, a character simply turns and runs up to his full movement rate. However, the fleeing character drops their defenses and turns their back to their opponent.
The enemy is allowed a free attack at the rear of the fleeing character. This attack is made the instant the character flees. It doesn’t count to the limit of attacks per round allowed, and initiative is irrelevant.
The fleeing character can be pursued, unless the enemy is blocked by another character or other obstacle.

• Prone:
  Prone characters present a very small target to missile fire, and gain a +2 bonus to AC. Melee attacks gain a +4 bonus to hit against prone targets. Prone targets lose their AC bonuses from Dexterity and shields.

• Sitting or Kneeling:
  Sitting or kneeling characters present a small target to missile fire, and gain a +1 bonus to AC. Melee attacks gain a +2 bonus to hit against these targets.

• Called Shots:
  Called shots are used to hit a specific target. For example, a character might need to smash a flask out of an opponent’s hand, or shoot a jewel out of an idol’s eye. The system doesn’t use hit locations, so such an attack does normal damage. It is assumed the character is already trying to kill their opponent as efficiently as possible.
  To make a called shot, the player must announce this before initiative is rolled. They suffer a +1 penalty to their initiative (time spent aiming). When the character acts, they attack with a penalty of -4 to their roll. Some targets are so small that they require larger penalties, up to -8.

Characters with the Precision Blow, or Precision Shot fighting styles, can get a +1 to hit on called shots. Those with the Weakness Identification non-weapon proficiency, can make use of called shots to do additional damage.

There are some conditions that can be achieved by using a called shot. A character may attempt to blind an opponent by attacking their eye, but such a small target suffers a -8 to hit. Such blindness would be on one eye, and is permanent until healed. Depending on how much damage the attack does, it may do more than blind them.

There is also another advantage to called shots: When attacking an opponent wearing armour with exposed body parts, one can attack those parts with a called shot to ignore their armour value to AC. So, while you suffer a -4 to hit, it is targeting a spot with an AC total that doesn’t include their armour value. Clearly, this tactic is more useful against opponents wearing medium or heavy armour. This tactic might also be useful against monsters with body parts that have a weaker AC.

• Mounts:
  Mounts provide the rider with a +1 bonus to attack rolls when fighting unmounted opponents.
  Unmounted characters suffer a -1 penalty to hit against mounted opponents.
  Riders can spur their mounts to attack, charge, and trample their opponents.

• Acrobatics:
  Some characters are proficient in Acrobatics. This proficiency allows them to tumble, vault, roll, dive, somersault, and flip through an area. Tumbling can only be done if the character is lightly encumbered or less.
  A character with acrobatics can improve their AC by +4 for a round, by tumbling around as long as they have initiative. This is a full move action, they must forgo all attacks for that round.
  This type of movement can be done in a straight line, to get from one point on the battlefield to another. The distance covered is the same as their regular movement. If the terrain is uneven or particularly difficult to cross, the DM may rule that it isn’t possible, or that the movement rate is slowed.

A character with Acrobatics can also improve their unarmed attacks (CMB and CMD) by +2.