Mechanoids have a 100% chance of being killed upon being downed, unlike humanoids. Pawns are downed if they drop to <15% mobility or <30% consciousness (data processing). This means the weakpoint of a lot of mechanoids are actually their legs, because any mechanoid that falls down auto-self-terminates. You don't even need to destroy the legs, just do enough damage to drop their mobility.

There's also a kill point from total damage. It's something like 150 on a size 1 creature like humans, but it scales based upon size. (For example, sythers and lancers also have size 1, while centipedes have size 3, and would take 450 damage to kill from raw damage.) For living creatures, it doesn't count blown-off limbs, and I haven't tested on mechanoids, but a lot of the time, you can just hit that "overall damage" threshold on a mechanoid.

I was aware that lowering consciousness or movement below a certain value leads to the death of mechanoids. But I didn't know about "There is also a kill point from total damage", although I suspected that something like this exists, especially noticeable on the huge creatures from V.O.I.D. whose body size sometimes reaches 30. But still, thank you very much for the explanation. Maybe there is some way to disable "There is also a kill point from total damage"?