Types Of shots
If one character is taking the initiative (rounding a corner, emerging from cover to shoot, ...) they will have an advantage because they know what to expect in the exact timing. This gives them an initiative bonus of 5 or 10 depending on how ready the target is for such an action.
In general, if one character is more aware of the specific timing of a shot (usually because they are the one rounding the corner, emerging from cover to attack, etc) they will receive a +5 or +10 on their react or tactical movement roll.
Declared and fired in the same tick. Generally point shooting, vs Dodge or Covering.
When two people are trying to shoot at each other at the same time. Reaction shots are Multitasking between React and Point shooting. The higher react role determines who fires first.
Resolve the first shot, with point shooting vs dodge/covering. The lower react is then allowed to fire, unless they are completely dropped by the first shot. They however suffer a -5 per threshold of the hit.
In quickdraw situations, or when you need to bring your weapon to bear, you must also multitask with handle, the lower of your react and handle rolls is used to determine when you fire.
In situations where you are ready for trouble but don't know exactly where it will be (coming around a corner for example) use Target instead of React.
Aimed shots are declared against a target and resolve the next tick or later. Aimed shots are made using aimed shooting and carry a bonus of at least 10.
You may also aim at a specific area and look for targets emerging. Declare it one tick, your aim becomes ready the next tick. If a target presents itself you may shoot at it with react and aimed shooting. You are considered to be expecting trouble from that area, so people emerging there do not receive the normal initiative bonus.
Shooting at point blank (for your weapon) offers a +10 on shooting rolls. Each range increment out imposes a -5 on point shooting rolls or -2 on aimed shooting. Cumbersome weapons have a minimum range and will require multitasking a handle roll to use inside that range. Use the lower of (point shooting, handle+10). Rough minimium ranges are .5m for pistols, 1m for carbines, 1.5 m for rifles, and 2m for heavy weapons.
As cover allows, you may choose to be open or closed against a given arc for each tick. If you are closed for an arc, you may not be fired on from that arc, but may not fire in that arc either. You probably retain some perepheral attention to what is happening there, but will generally not have a detailed understanding of what is happening in that arc.
The default assumed state is that you are closed (hiding behind your cover). GM will tell you if things you want to do require opening. Shooting usually requires opening, though you can lay covering fire at a -10 if you know where your target is reasonably well (sticking your weapon out and firing blindly).
If you are open, you still receive a +10 on covering rolls (may be a different number depending on quality of cover and exact situation).
If you move to gain an arc of fire against someone in cover you will multitask point shooting with tactical movement (generally sprint or tumble) opposed by their react roll.
You can lay down covering fire against someone. This forces them to multitask a covering roll with anything they choose to do that needs to expose themselves to the arc you are covering. Make a sustained shooting roll with a bonus/penalty determined by the number of bullets you are firing. If they fail the covering roll against this sustained fire, they are hit by fire.
Because you do not know exactly when the target is going to emerge, cover fire rolls take a penalty unless you are dumping enough lead that it does not matter.
1 shot every 4 ticks: -20
1 shot every 2 ticks: -10
1 shot every tick: -5
Rates of fire higher than 1 per tick probably require an automatic weapon
2 shots per tick: +0
4 shots per tick: +5
8 shots per tick: +10
Rates of fire higher than 8 shots per tick are not possible with normal automatic weapons, you need a specifically high firing gun.
16 shots per tick: +15
32 shots per tick: +20
A distract roll can often be used to gain initiative.
If you are flat footed (not moving or at least in a combat stance so you can move quickly) you take a -10 on dodge rolls .
Example: B moves out from cover to get a shot off at A
A: A's roll, B: B's roll, T: the relevant threshold size
B declares they are moving out at a tactical trot to attempt a shot at A
B: rolls Point Shooting vs A's covering
B > A: B is able to get a clear shot before A notices and/or is able to bring a weapon to bear
A takes damage as normal for the thresholds
A > B but < B+T: A retreats further into cover and avoids being hit
A > B+T: A notices B's approach and shoots before A can
Roll A's point shooting vs B's Tactical Trot, hits as normal on B for thresholds
Point shooting rolls when approaching under observation take a -10 penalty, however a combatant can generally lay down cover fire for themselves against one opponent, removing the penalty (expending an extra 3 rounds of ammunition)
If you must move through more than one opponent's line of fire, you have to roll Tactical Trot -10 vs other's React, or they get a shot off at you. The -10 can be removed if you have an ally laying covering fire on a given opponent.
If the opponent you are approaching's attention is elsewhere, they must roll covering and react to defend and take the lower.