Construciton robots dying from ground fire trying to repair walls?

[Gazer75]

I've noticed that when they try to repair a wall and there is fire on the ground from flame turrets they basically die from the fire below.
Is this intended? Makes the flamethrowers kind of bad to use as they basically destroys your drones.

[Fel]

Usually it's not fire but spitters that destroy bots, but either way it can be solved fairly easily by placing the roboport further back.
Construction robots use the wider area so that way they take longer to reach the damaged items and the fight is generally finished by then.

Flamethrower turrets are anything but bad since they allow you to kill spitters early on (thanks to the fire that stays on the ground) unlike laser turrets that can only damage the closest enemy (gun turrets don't have the range to even fire on larger spitters).
This means that the potential damage on your walls and turrets are greatly reduced without needing.

In theory, the damage to your walls should be minimal at best, most of the damaged walls should be on the defensive wall instead of the dragon teeth, meaning that the fire should rarely be an issue for your drones.

[schnappkatze]

Originally posted by Fel:

(gun turrets don't have the range to even fire on larger spitters).

This seems to be outdated information, the wiki has Behemoth Spitters at a range of 16 and gun turrets at a range of 18, they should reach them. Maybe it was different in an earlier version?

[knighttemplar1960]

Originally posted by schnappkatze:

Originally posted by Fel:

(gun turrets don't have the range to even fire on larger spitters).

This seems to be outdated information, the wiki has Behemoth Spitters at a range of 16 and gun turrets at a range of 18, they should reach them. Maybe it was different in an earlier version?

The wiki is correct. I use a double wall set up instead of dragons teeth. My gun turrets are set up so that they are 17 tiles from the outside edge of the outer wall with laser turrets and flame thrower turrets behind those. The biters are faster than the spitters and they activate the flame throwers but out run the flame until they hit the outside edge of the wall at that point they are burned by fire, zapped by laser, and shredded by bullets. The spitters (that have less health than the biters) then hit the fire that the biters trigger and are usually dead when the lasers start firing only when there are a huge number of spitters do the gun turrets fire on the spitters and the spitters still can't get into range to spit on the turrets.

The construction bots do take damage from the fire and you do have to replace some on occasion. The ones damaged by the fire cause other bots to come out and repair them and those bots then take damage too which deploys another bot. There are 2 ways to solve that either leave your robot speed slow so the fire is out before the robots arrive (not ideal) or use infinite research to really speed up your robots so that they go out and back faster and spend less time in the fire. I also make sure that the very edge of the construction range of the roboport is at the maximum range of the outside edge of the defenses.
https://steamcommunity.com/sharedfiles/filedetails/?id=2602877802

[Нагризолич]

It is intentional, of course, but there is a way to lower drone losses to a minimum.

Also, if you want to repair your defences with drones, and you will have to do it when behemots start appearing, keep in mind that flamethrowers kill your drones like flies, so this device is practically necessary unless you want to automate drone production to replace repair bots with 4 repair packs that will die after every attack.

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

Save it for much later in game. You need logistics bots for it to work, one or two stacks should be enough. If you have a lot of repair packs - increase the number in arithmetic combinator from 600 to no more than 4800. If your stuff is getting destroyed with it - change the number in constant combinator from 24k to a smaller number, like 18 or 16k.

[Hedning]

Originally posted by Gazer75:

I've noticed that when they try to repair a wall and there is fire on the ground from flame turrets they basically die from the fire below.
Is this intended? Makes the flamethrowers kind of bad to use as they basically destroys your drones.

The flamethrower is the only aoe turret. It is required for large behemoth attacks, or at least you'll lose a lot more resources trying to defend with other turrets.

My solution to bots dying to fire is to have only a few construction bots at any one time covering a large section of wall.

Bots never need to repair a wall while an attack is going on, and with more pollution you'll get larger attacks rather than more frequent attacks, so even a few bots never get overburdened, but having just a few bots means they will be far away and thus take a long time to reach the damaged part. Even a large attack should be over by then.

Of course sometimes the attack happens when the bots are already nearby and then they'll die. Bot death is unavoidable unless you clear the entire pollution cloud and turn off biter expansion (rail world).

[Gazer75]

So I tested with max range roboport, but with speed upgrade it doesn't matter. They still go over to repair way before fires die out. And with the large attacks late game at 0.99 evolution, the robots easily get to the damaged wall at the end of the attack if not before.
Maybe if I had not upgraded robot speed it would make them slow enough. But that makes robots kind of useless for other tasks.

I've tested with 3-4 deep laser and the survivability of robots is lower as it takes to long to kill spitters.

Yet to test guns with uranium ammo in front, but my experience is these turrets die to fast from behemoth spitters.

Tbh there should be a late tech that increases robot hp.

[Hedning]

Originally posted by Gazer75:

So I tested with max range roboport, but with speed upgrade it doesn't matter.

That's why I said I use just a few robots for a large area, then they are usually multiple roboports away.

[knighttemplar1960]

Originally posted by Gazer75:

Yet to test guns with uranium ammo in front, but my experience is these turrets die to fast from behemoth spitters.

Gun turrets out range behemoth spitters by 1 tile. You can place gun turrets so that they are out of spitter range and can still hit behemoth spitters. If that weren't true it would be nearly impossible to get the raining bullets achievement.

Replacing the occasional construction robot is just a fact of life but by the time you can make them you should have enough of a surplus to replace the infrequent loss.

[Gazer75]

Originally posted by Hedning:

Originally posted by Gazer75:

So I tested with max range roboport, but with speed upgrade it doesn't matter.

That's why I said I use just a few robots for a large area, then they are usually multiple roboports away.

Not when the perimeter wall is at chokepoints that can be covered by 2-3 roboports.
And for larger areas robots still reach repair spots pretty fast. If I could tell them to not repair walls and just the turrets it would probably be easier. You could have the walls stored far away.

Originally posted by knighttemplar1960:

Originally posted by Gazer75:

Yet to test guns with uranium ammo in front, but my experience is these turrets die to fast from behemoth spitters.

Gun turrets out range behemoth spitters by 1 tile. You can place gun turrets so that they are out of spitter range and can still hit behemoth spitters. If that weren't true it would be nearly impossible to get the raining bullets achievement.

Replacing the occasional construction robot is just a fact of life but by the time you can make them you should have enough of a surplus to replace the infrequent loss.

I can replace them just fine, that is not the problem. I just find it annoying that they are stupid enough to kill themselves in friendly fire. They should at least have some late upgrade to make them fireproof or something if they can't avoid the fire.
As it is now they have 100? hp and pretty much die instantly if they attempt to repair a wall that also have fire.
I can loose 5+ robots per big attack if the wall sections get damaged enough. Some die from spitter attacks instantly as well it seems.
The alarm is getting kind of tiring.

[knighttemplar1960]

Originally posted by Gazer75:

Originally posted by knighttemplar1960:

Gun turrets out range behemoth spitters by 1 tile. You can place gun turrets so that they are out of spitter range and can still hit behemoth spitters. If that weren't true it would be nearly impossible to get the raining bullets achievement.

Replacing the occasional construction robot is just a fact of life but by the time you can make them you should have enough of a surplus to replace the infrequent loss.

I can replace them just fine, that is not the problem. I just find it annoying that they are stupid enough to kill themselves in friendly fire. They should at least have some late upgrade to make them fireproof or something if they can't avoid the fire.
As it is now they have 100? hp and pretty much die instantly if they attempt to repair a wall that also have fire.
I can loose 5+ robots per big attack if the wall sections get damaged enough. Some die from spitter attacks instantly as well it seems.
The alarm is getting kind of tiring.

Part of the issue you are experiencing is the way that flamethrower turrets works. If you use choke points you are more likely to lose robots because of the damage build up in a choke point.

The flame thrower does 3 types of damage.

1. Ignition damage. Any target that is directly targeted by the flamethrower turret takes 100 ignition fire damage/sec for up to 30 seconds. This type damage can't affect the player or the robots since they can't be targeted by the flamethrower turrets.
2. Contact damage which is 3 fire damage/sec.
3. Fire on the ground which is 13 fire damage/sec and lasts 2 seconds.

A flamethrower targets the closest non-ignited enemy first and then goes on to target all non-ignited enemies. Once all enemies are ignited the turret targets the closest still alive enemy.

This damage is location specific and also turret specific. Multiple turrets firing on the same tile do not increase this damage faster. If enemies are in one particular tile and the turret keeps firing at that location the AOE damage (ground fire) increases in both size and intensity until it reaches a maximum duration of 30 seconds and a cap of 6 times base damage.

All of this is additionally modified by both damage increase for flamethrower turrets and flamethrower ammunition which is multiplicative rather than additive.

If you want to save your robots then you want to depend on ignition damage since no bug can survive it even without any of the damage researches (a behemoth biter has 3,000 health and no fire resistance, if it is ignited by base damage flame thrower turrets using crude oil, 100 ignition damage/second for the 30 seconds will kill it). Damage researches just means that it happens faster.

Choke points concentrate ground fire damage and make the fire burn hotter and last longer. If you can design your walls to spread the bugs out instead of concentrating them in one spot the ground fire will be out before the robots arrive or will have diminished enough for them to survive the contact damage and the ground fire. It might seem counter intuitive but the way to do this t\is to increase the damage bonus for you flame throwers so that the ignition damage kills the bugs faster so that less ground fire is created.

As I previously mentioned speeding your robots up means that they spend less time taking contact and ground fire damage.

Robots have 0/85% resistance to fire damage but have no resistance to acid damage. A behemoth spitter does 60 contact acid damage and then 360 acid damage/sec after that so a robot lasts less than 1 second.

TL:DR

The five most effective strategies for saving your robots are:

1. Damage researches so that ignition damage kills the targets faster and AOE build up is reduced.
2. Faster robot speeds so that they spend less time in the ground fire.
3. Spreading waves over a larger area rather than a smaller area/choke point so that you are depending more on ignition damage and less on ground fire damage.
4. Increase the number of flamethrower turrets in a given area to speed up ignitions and to keep a single turret from concentrating fire on one specific place and building up a huge bonfire that lasts too long and does too much damage after all enemies are killed.
5. Layer other turret types with the flamethrowers to kill bugs faster and reduce ground fire build up.

Its much cheaper in terms of resources to replace a couple extra walls than a single bot.

[shadain597]

Originally posted by Gazer75:

I can replace them just fine, that is not the problem. I just find it annoying that they are stupid enough to kill themselves in friendly fire. They should at least have some late upgrade to make them fireproof or something if they can't avoid the fire.
As it is now they have 100? hp and pretty much die instantly if they attempt to repair a wall that also have fire.
I can loose 5+ robots per big attack if the wall sections get damaged enough. Some die from spitter attacks instantly as well it seems.
The alarm is getting kind of tiring.

By the way, there are mods that can make this less annoying, if you are so inclined. I think I've seen both fireproof bots and a mod for walls that can't be repaired but automatically heal-over-time.

[knighttemplar1960]

Originally posted by shadain597:

Originally posted by Gazer75:

I can replace them just fine, that is not the problem. I just find it annoying that they are stupid enough to kill themselves in friendly fire. They should at least have some late upgrade to make them fireproof or something if they can't avoid the fire.
As it is now they have 100? hp and pretty much die instantly if they attempt to repair a wall that also have fire.
I can loose 5+ robots per big attack if the wall sections get damaged enough. Some die from spitter attacks instantly as well it seems.
The alarm is getting kind of tiring.

By the way, there are mods that can make this less annoying, if you are so inclined. I think I've seen both fireproof bots and a mod for walls that can't be repaired but automatically heal-over-time.

There are mods for both fireproof bots and indestructible bots.

[Nonotorious]

My bots almost never get hit by anything. https://steamcommunity.com/sharedfiles/filedetails/?id=2874915049

Occasionally i will get a spitter at the corner that found a sweet spot to fire at bots fixing the outer wall but they usually move in slightly to chase the bots returning and get fried eventually anyway, i have it set up to automatically replenish bots under a certain amount.