When combat begins, everyone rolls a d20 and adds AGI. This is your Initiative, which determines turn order; people with higher initiative move sooner.
When it is your turn, you can take a number of actions determined by your AGI (usually 2). Actions are any one of the following:
Deal damage or status effect to a foe (Can only be done once per turn)
Use any other skill or class feature (Each skill can be used only once per turn).
Move 30 feet in gravity or EFF+AGI*5 squares on map in zero-g.
Hand an item to an ally.
Use an item.
Assist an ally – ally takes plus 1 to Skill and EFF rolls for one skill; you need the skill they are using in order to assist.
Sustain a Psychic Power
Hold action: save an action to be used at any point you choose between now and your next turn.
Some actions, like psychic powers, take your whole turn. Other abilities may give you additional combat actions. In space, your ship has a velocity (how fast it is going), and a direction it is travelling. Unless you use Piloting skill to change the course, the ship keeps going in that direction.
These combat conditions apply to everyone:
Counter – Hold an action; later, use the same skill as an enemy at the same time. If your roll is higher than their roll, your enemy’s action is negated. If your roll is higher than the enemy’s passive defense, gain the normal benefit of using that skill as well.
Flank- If you and an ally are surrounding a foe on opposite sides, take plus 1 to Fighting against that opponent.
Charge (whole turn action)- Move in a straight line towards your foe, and take plus 1 to Fighting against that opponent.
Uphill – Fighting from a higher elevation grants you plus 1 to Fighting.
When you are attacked:
Your enemy rolls with PHY or AGI depending on if they attacked with brute force or precision, respectively. They roll against your Fortitude if they attacked with PHY, and against your Reflexes if they attacked with AGI.
If they roll a 7 or less, their attack Fails.
If they roll more than 7 but less than the passive defense they are rolling against, their attack Misses.
If they meet or beat your passive defense, their attack Succeeds and goes on to Armor Break. The enemy rolls their EFF for damage and subtracts your armor. You are wounded for any damage your armor does not block. To deal status effect instead of damage, EFF rolls must exceed armor by at least one. (Getting at least one damage past an enemy’s armor is considered a successful Armor Break.)
When you attack:
Several different skills can deal damage.
Roll a d20 and add the appropriate Stat.
If your roll+Stat meets or beats the corresponding passive defense, you Succeed and go on to Armor Break.
Roll EFF as described in the skill or ability. To deal a status effect instead of damage, you still need to Armor Break.
Character death – If your wounds are equal to or greater than your Hit Points, you are dead. Note the time, because someone who succeeds Medicine against your Fort can resuscitate you back to 1 HP. If you aren’t revived in 30 minutes or put into stasis somehow, your character dies. Roll a new character and join the crew when it makes sense in the fiction.