I toyed around with the Unit Tester to make a demo of how useful focus fire is and I found out that in surprisingly many situations it'd be a bad idea to take all your ranged units and focus fire whilst queuing attack targets. The problems are:
1. Large amounts of projectile firing units will overkill and waste a lot of DPS. 2. Ground units take longer to build an arch when focus firing and while the units walk around they'll waste DPS. Actually also air units that focus fire might float away further than attack-moving air units and thus cause a loss of DPS. Though shoot-n-scoot should work.
The best units for focus fire would be air units that don't overkill, I think there are none. In many cases unit positioning, building an arch or flanking, will be more effective. Also, in many cases you're better off just not focus firing, so APM should be invested in other activities.
Testing with 10 of each: muta-vs-muta, viking-vs-viking, phoenix-vs-phoenix and marine-vs-marine proved that in almost all cases focus firing with the entire force was detrimental. One could try and focus fire with smaller groups though that demands more APM than I have to test.
In the video, it's not the fact that you focus fire that has the biggest impact. What you do is you clump up your units so the attacking force gets a concave on you. Also, in the phoenix clip, the un-microd phoenixes were also focus-firing by sheer luck.
There was some testing done during beta on the smart-firing system, and I know that if you shift-queue targets for focus firing, any attacks that would overkill the first will go to the next target, and so on.
On August 22 2010 05:10 MoNoNauT wrote: There was some testing done during beta on the smart-firing system, and I know that if you shift-queue targets for focus firing, any attacks that would overkill the first will go to the next target, and so on.
On August 22 2010 05:10 MoNoNauT wrote: There was some testing done during beta on the smart-firing system, and I know that if you shift-queue targets for focus firing, any attacks that would overkill the first will go to the next target, and so on.
^this
only for attacks that don't have a projectile and hit instantly - i.e. tanks, immortals etc
EDIT: from my experience when you're fighting a large group of units ff actually makes it worse, positioning is key
I'm not sure if I understood you properly during the phoenix part, but Phoenixes can attack while moving, like diamondbacks, so moving doesn't cause them to waste DPS.
I think this is pretty telling, and probably one of the mistakes a lot of people make by trying to get the most out of their units. Over micro basically. In almost cases its better to be firing, then to be moving getting ready to fire.
On August 22 2010 05:30 TedJustice wrote: I'm not sure if I understood you properly during the phoenix part, but Phoenixes can attack while moving, like diamondbacks, so moving doesn't cause them to waste DPS.
I focus fired the phoenixes from nearest to farthest and some of my phoenixes floated away when firing on the forward enemy unit. Now to engage the next phoenix, they had to move to get in range. Moving to get in to range wasted DPS.
On August 22 2010 05:10 MoNoNauT wrote: There was some testing done during beta on the smart-firing system, and I know that if you shift-queue targets for focus firing, any attacks that would overkill the first will go to the next target, and so on.
Like asdfjh said, the only units that smart-fire are Tanks, Marines and Immortals. These ground units will still not benefit from shift-queuing and in fact will lose because it'll ruin their positioning (except that sieged tanks are static anyways). Take 10+ tanks (not sieged), marines or immortals in a mirror skirmish and see how bad positioning kills your units (I show this in the marines demo in the vid). If you have only 3 units that are always going to be in range of the rest - shift-queuing works, but it gets bad when you have more units wasting DPS just to get in range while attack-move just builds an arch.
I urge you to test this yourself if you don't believe me.
On August 22 2010 05:03 Nihilnovi wrote: In the video, it's not the fact that you focus fire that has the biggest impact. What you do is you clump up your units so the attacking force gets a concave on you. Also, in the phoenix clip, the un-microd phoenixes were also focus-firing by sheer luck.
I tried focus-firing without clumping just now and got the same results - randomly one side wins with only 1 phoenix left. The randomization is caused by the overkill not being consistent as it has to do with very specific timing. So clumping wasn't detrimental to the test imo.
Plus, these are air-units which are supposed to be the best for shift-queuing focus fire, and they're not. Ground units suffer even more.
I think the main lesson is that you should only focus fire groups of 3-4 units at a time if you want to really deal the damage. If you don't have the APM for that - don't focus fire at all.
It becomes a major factor when dealing with high priority targets. FF is used to either be telling in small unit battles, where the enemy losing a unit before you do in otherwise close scenarios is a bigger loss, or where the enemy has one or two units wrecking your composition with a large group of other units serving as lesser DPS and meatshields.
Good example is stalker vs stalker immortal, marine marauder vs stalker zealot collossus, and any kind of capital ship composition or anti-tank measures.
Best use of focus firing tends to be not trying to have every single unit attack one target, but having smaller subsets focus units near them. If you have e.g. 20 stalkers, you might only want 6ish on the right to focus a few things, while another 6ish on the left focusing another thing. You have to be careful doing this, though. Don't blindly shift queue because you can easily get destroyed by someone smart enough to pull units back (e.g. blink backwards).
You should focus fire with small amount of units. With big groups, the advantage of focus will be outmatched by the fact that units will keep trying to move into range and waste shooting time.
yes, there are probably discussions of dragoons vs dragoons in the BW forums discussing a similar problem. what really would help to know is how many shots you need to 1- or 2-shot the other guy's units, and only focus fire with that many of your units, and only after you have a good arc
in sc2 I would guess it's important to know how many vikings it takes to 1shot other vikings, for instance.
phoenixes should not be focus firing AT ALL because they can attack while moving, so no wonder it doesn't work as well. it's possible to pseudo-focus a target without creating overkill by simply stacking phoenixes and microing so that the target you want to focus is in the front but ideally you would not sit still with phoenixes, because there's really no reason to ever stop moving except having to control another unit.
you should focus fire primarily when there's a target worth focusing. i'm not sure how it gets more complicated than that, it's just a matter of figuring out what is worth focusing. a majority of the time, most of your units should just be a-moving in battle, ideally with a bit of micro to spread them out like you did with the marines.
you could say that in a group of pure marine, the value targets are the ones with lower life, because eliminating them removes DPS. what you would do is not make your entire army focus on them, but have a couple units double-team low HP units while most of your forces wittle down the opponent's forces HP to provide more value targets, while simultaneously retreating your own low HP units so that you force the opponent's a-moving units to switch targets and spread their DPS out without getting actual kills.
beyond that, focus fire is very composition dependent (because some units are valuable to focus just by being there), situation dependent, and really can't be accurately be measured by unit testers because both players should be microing which opens up more situations where a unit will be low HP (due to good micro) or in a poor formation and therefore worth focusing. the situations that happen in a game don't happen in unit tester because you can't control both sides.
i'd take unit tester results with a grain of salt, they don't give you too much applicable information if there are situations where one person controlling each side would change how the unit match up works, which is nearly always the case. i basically only use it to measure how many X is needed to beat Y in an a-move battle, what differences do upgrades make, and how cost-effective the battle is for both sides. even that is not enough to go into an actual game and say "well it worked in unit tester!" because in unit tester, units come out ASAP but often times the actual timing of tech will make match ups that work in unit tester unrealistic.
Completely depends on which you and your opponents have. If you are in a big TvP battle with Marauders vs gateway units and colossi then of course its always a good idea to try to run forward and snipe off the colossi first. At least in almost all cases. If there are no special units you want to take out early in the fight and the arcs are getting so big that all your units cant get in range on one of the opponents units without breaking the arc then focus firing is obviously a bad idea.
Focus firing is so situational. If you opponent is dropping you then you should probably try to kill the dropships first if he hasn't unloaded all his units. If you have a marine/marauder army and you opponent has air units then it's often a good idea to make sure that the marines keep firing at the air units instead of ground so you don't end up with marauders vs mutas when the enemies ground units are dead. If you are using hellions then obviously its a good idea to make sure they are firing at small units since they deal so much more damage against them. Sometimes it has more to do with positioning going into the battle and rearranging you positioning during the battle than it has to do with focus firing.
Generally I tend to focus fire only in two situations.
A - There's something specific that I need to kill, like that 1 Immortal or 1 Colossus in an early/mid game Protoss comp.
B - I want to be sure to get something that already has very low HP from a previous battle.
When it's a large battle later in the game, I tend not to focus fire and worry more about active abilities or stop-fire micro and other general positioning concerns.
By the looks of this discussion, I guess I am doing it the right way!
I've intuitively noticed that mass marauder (i.e. 20+ marauders only) tends to suck more than an equal amount marines/marauders. I suspect this is because, like you said, focus firing with projectile-based units is not incredibly efficient. Once you get a ton of marauders, they're kind of inherently focus-firing automatically just because there are so many of them.
Good thread, and gives me more to think about on this line of thought.
I think part of the mass marauder problem is just that sometimes people don't realize that Marines do more damage per cost to Light units than Marauders do.
But yes, this is interesting, I didn't realize that the projectile delay could result in lost damage.
On August 23 2010 09:20 Ketara wrote: I think part of the mass marauder problem is just that sometimes people don't realize that Marines do more damage per cost to Light units than Marauders do.
But yes, this is interesting, I didn't realize that the projectile delay could result in lost damage.
I thought about this, but it seems to happen even against stalkers, roaches, etc. I think that the density of marauders contributes to this effect.
Yeah, Marauders are bigger than Marines so it's more difficult to get a concave.
Plus, since the Marines range is shorter, they naturally run ahead of the Marauders, making it even easier to get a good concave. The two units really do mesh together marvelously.
But we should keep on topic.
How does this focus fire problem affect melee units? Is it more detrimental to FF say, Zerglings?
This is really good to know, thanks for bringing it to my attention OP.
I would argue that focus-firing makes a big difference in small-scale battles, though. A common scenario I run across this is when I'm playing a ZvZ game, and my first batch of 3-4 mutas goes against an equal number of my opponents mutas. In that situation, overkill is not a much of a factor due to the small number of units involved, and therefore focus-firing makes a big difference.
Edit: So we know that non-projectile attacks don't have overkill. How about void rays?
On August 23 2010 09:50 Mindspider wrote: This is really good to know, thanks for bringing it to my attention OP.
I would argue that focus-firing makes a big difference in small-scale battles, though. A common scenario I run across this is when I'm playing a ZvZ game, and my first batch of 3-4 mutas goes against an equal number of my opponents mutas. In that situation, overkill is not a much of a factor due to the small number of units involved, and therefore focus-firing makes a big difference.
Edit: So we know that non-projectile attacks don't have overkill. How about void rays?
VR's attack with quite a high speed so i'd say that isn't much of an issue.
In a perfect micro world, you would focus fire using only the exact number of units needed to kill a single enemy unit without sacrificing unit positioning (making your unit have to move to fire on the selected unit when another enemy unit is within it's attacking range allready).
For example: It takes 9 marauder attacks to kill a stalker. You should select only 9 marauders to focus fire down stalkers. However it's quite hard to get 9 marauders in an arc to hit a single stalker without sacrificing a little time to get the marauders in position.
In general I like pushing out against protoss with 20 marauders. I have them in 2 control groups of 10 each, and use a 3rd control group to select them all. You can use all 20 to focus fire zealots down in one shot as it takes 17 hits to kill a zealot. For stalkers I focus fire with 2 seperate groups. It works well at the start of the battle until you start losing units, then it becomes a bit inefficient as your full selection would overkill a unit and your partial selection wouldn't be enough to kill a unit.
Focus fire is always risky though. One misclick and you could put yourself in trouble. With fast firing units such as marines, so many times I've focussed a target and changed target just before it died allowing it to get a few more shots off before i realise. But even worse, I'd then use my whole selection to finish the remaining 5hp left on that unit causing like, a 95% overkill on it ;/ It's almost like my failed focus firing is providing my enemy with free 'perfect micro', keeping a single unit alive on nearly 0 HP.
interesting, focus fire works in small situations and with units that dont have a fast attack rate(not very fast like a marine or pheonix) but if your have a large - mid scale theres no point to the focus fire becasue as you said 1) its going to overkill and 2) you'll waste dps by moving around. very interesting indeed though
EPT
