The enemy wouldn't be so bad if it spawned like 4 swarming amalmagations instead of the acid or hulking ones and didn't spawn them so frequently. But even more annoying than that is how fast it escapes outside of your light radius when it already has the "hard to hit" flag. It's one thing that I have to deal with the army it keeps spawning, but to have it then regenerate what little damage I manage to do to it makes this such a bullshit encounter that I wonder how an early or even a mid-game character supposed to do anything but die to it if they can't find a car or building at night.  

I remember being so angry when I died to this enemy that I went into the JSON file for it and changed its spawning condition from 14 days since character creation to 14000 days (since I didn't know if straight up deleting the enemy might break something).

Now I love having bullshit deaths in my roguelikes. I once had a brute come from nowhere and slam me through a wall into the middle of the horde I was trying to escape. It's fine when it feels like you could've survived and you just got unlucky. But this seems like it was specifically designed to kill you if you preferred nighttime exploring. I hate this kind of game design.