While playing with this mod in addition to Krastorio, I noticed that while most enemies do negligible amounts of damage...
the big poison worms need only to hit with one single shot and the dot kills anything (players, even tanks!) in the manner of a few seconds.
I am ~80% percent sure it's the poison worm, not acid or fire.
Digging through the files, I found out that in the mod, the poison cloud has "action_frequency = 5" while the vanilla
game poison capsule cloud has "action_cooldown = 30".
Or more likely the poison sticker which seems to do a wopping 30*60 = 1800 dmg over 30 seconds with no
"breaths-air" flag and in the base game nothing has resistances to poison damage...
I am not sure if this a bug or deliberate, but if it's the latter it seems like a weird design choice to me.

I have also experienced this. There is definitely something wrong with the big poison worms.

Maybe Bob meant for the poison-sticker to stick to the poison cloud rather than the player.

I was so frustrated by this I hacked my copy of the file to do 1 dmg/sec for 8 seconds rather than 60 dmg/sec for 30 seconds. In case anyone wants to do the same, here's how I did it:

In entities.lua, I renamed "poison-sticker" to "poison-spit-sticker" (so as not to conflict with bobwarfare). Then I changed duration_in_ticks to 60 * 8 and damage_per_tick amount to 0.0166666666666668.

Then in projectiles.lua, I did a search and replace of "poison-sticker" to "poison-spit-sticker"

I hope Bob fixes this one.

Yeah hitting this as well. One sip of poison and it's death no matter what.

Literally ruins the game, cant approach a base without any getting obliterated by a poison worm