Copied the error text below, seems to crash randomly after a little while and give this error message. Also, just experienced a weird extreme over-spawning issue where the FPS tanked to like 1 frame every few seconds for a few minutes, and then a few minutes later a huge crowd of thousands of biters appeared, took close to a dozen nukes to kill them all before they made it to my base, with the first half of the nukes freezing the game for like 10 seconds each explosion.

Currently have most of the settings set to around or slightly below 1.5x of default.

614.030 Error MainLoop.cpp:1449: Exception at tick 45305682: The mod More Enemies (0.3.1) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event more-enemies::on_tick (ID 0)
LuaCommandable API call when LuaCommandable was invalid.
stack traceback:
[C]: in function 'index'
__more-enemies/control/service/spawn-service.lua:176: in function 'do_nth_tick'
more-enemies/control/controller/spawn-controller.lua:63: in function <more-enemies/control/controller/spawn-controller.lua:39>

I managed to make a save a few seconds before the freezing and found where it happened.

Just a few seconds before, enemies gathering like normal: https://i.postimg.cc/d1qVxk67/factorio-more-enemies-bug-1.png

Right after the freezing started: https://i.postimg.cc/s2P2m9Yd/factorio-more-enemies-bug-2.png

Right after the game went back to normal: https://i.postimg.cc/QMZtcnWJ/factorio-more-enemies-bug-3.png

The mod settings I'm currently using: https://i.postimg.cc/rFcC8Qp3/factorio-more-enemies-settings.png

Thank you very much for reporting this! Let me take a look and dig in to see what I can find.

The spawning/cloning shouldn't be that egregious given your settings, so something may well be off.

Few questions for you:
- What is your evolution at currently?
- Is the crash repeatable, or random?
- Have you experimented with the log settings to see what might be going on? (No worries if not on this one, those settings are mostly for myself)

614.030 Error MainLoop.cpp:1449: Exception at tick 45305682: The mod More Enemies (0.3.1) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event more-enemies::on_tick (ID 0)
LuaCommandable API call when LuaCommandable was invalid.
stack traceback:
[C]: in function 'index'
__more-enemies/control/service/spawn-service.lua:176: in function 'do_nth_tick'
more-enemies/control/controller/spawn-controller.lua:63: in function <more-enemies/control/controller/spawn-controller.lua:39>

This seems to have been a simple case of not performing a validity check when there should have been one. Should hopefully have a fix out shortly for that. Thanks again for reporting it.

The over-spawning will take a bit more investigation on my part, apologies.

Evolution factor is currently 0.9654.
It happens 100% of the time a few seconds after I load back, but it could still be random and the point I saved is just past the initial random cause.

I set the mod log setting to Info and it printed 80MB of data (1.072 million lines) to the factorio-current.log file during the mass spawning event. I can send you the whole thing if you have some place I can upload a 80mb text file to...

Most of it is this line:

890.023 Script @more-enemies/libs/log/log.lua:249: Debug: "adding member to staged_clones"

Then these appears a bunch towards the end:

1073.324 Script @more-enemies/libs/log/log.lua:249: Info: "Found nil or invalid clone"
1073.324 Script @more-enemies/libs/log/log.lua:249: Info: {
group = "[LuaCommandable: UnitGroup(id=1838682, force=enemy) at [gps=-24.2,-375.2]]",
obj = "[LuaEntity: big-spitter at [gps=-2.3,-365.3]]"
}

1073.524 Script @more-enemies/libs/log/log.lua:249: Info: "Found nil or invalid clone"
1073.524 Script @more-enemies/libs/log/log.lua:249: Debug: "breaking from initial step of cleanup"
1073.524 Script @more-enemies/libs/log/log.lua:249: Info: "Starting iteration of _invalids"
1073.524 Script @more-enemies/libs/log/log.lua:249: Info: "Removing invalids"
1073.524 Script @more-enemies/libs/log/log.lua:249: Info: "Removing invalids"
1073.524 Script @more-enemies/libs/log/log.lua:249: Info: "Removing invalids"

Thank you for the follow-up. While I fixed the specific line the caused the crash for you, there were other cases where I needed to perform validity checks, which is likely why it continued to crash, apologies.

I am performing a review of my code to try and add any missing validity checks - found a few so far.

Additionally, I believe I have been able to reproduce the over-spawning you were experiencing with the same settings as those you provided. Trying to work out why exactly, but it appears that when the unit group forms, it starts cloning, and doesn't stop until it hits the configured maximum limit - hence the extreme lag and massive wave of enemies.

Hoping to have both figured out/fixed some time today.

Apologies again for the issues. Thank you for reporting them!

That's great. Also one other thing i noticed, if it's fixable. Several times I've come upon a nest, see the biters wandering around and then when i get close enough to trigger them the small group of behemoth biters just instantly divides in to a large group of like a couple dozen. I assume because of the cloning they're just all occupying the same space and have the same AI so until something changes they wander around looking like one enemy when there's a dozen in the same exact spot.

Would it be possible to apply some slight random variation to their position when cloning?

Absolutely, it's actually something that's been in the back of my head to implement, just haven't gotten to it yet; trying to fix bugs and get it stable first.

As of 0.3.4, hopefully the issues you've experienced should be fixed now.

In my testing, the spawning has been much more appropriate relative to the selected preset difficulty. Also, I added some slight randomness to the position of the clones when they're spawned, hope it helps.

Please do let me know if you experience any other issues