Formicarium saves each time there is no more mobs inside it

[The vegetarian ant]

the title may not be very clear, so I'll explain
when you are on your formicarium, you must have finished the third challenge in order to be able to spawn mobs, once it's done, you can put down a pheromone marker so you'll see if it moves, then save your formicarium, add some mobs and while your ants are fighting move your pheromone marker to somewhere else and when there is no more mobs, spawn a second wave of them, once they are killed you can load last save and you'll can see the pheromone marker changed of place, it is not where you placed it when you saved the game but where you placed it after killing mobs, that can be very problematic it cases where mobs have successfully hurt your queen without killing it, wich makes you load to a point where you need to wait for the queen to heal which is very long, but it gets worse, if by example you wanter to place a nursery somewhere but missclick and end up digging a hole right next to your queen or changing some royal jelly upgrade to test it and the game saves there, then you are good to get a new formicarium because this one is gonna be weak and / or it's gonna be a waste of royal jelly

 

[MikeSlugDisco]

Logged, a softlock here rather than a bug.

 

[JohnSlugDisco]

Ill take a look now see what is going down.

 

[JohnSlugDisco]

So the way it is currently set up is it saves on the start of you spawning creatures, it shouldn't save again until they are all dead so it is before the attack not after it.
I get what you are saying but without overhauling the save system (which we might do at some point) I think this is the lesser of two evils. If you spent a long time working on your formicarium and then spawned some creatures without thinking and they killed your queen you have lost all the progress since the last save.
For now it will remain as it is but I am not ruling out re-doing the save system at some point (just not yet)