>>36482
You can already behead them with the saw and the axe. For the longest time I was convinced you couldn't because the spot you need to click to get it to work is so fickle.

I like to use the axe since it's much faster and I wait until the vibrator has them peaking.

Unfortunately since the game doesn't know anything about depth, the head is immediately trapped between the two arms and doesn't topple down. If you cut the arms off so it can fall, then it can fall outside the map where you can't pick it up or do anything else with it.

Also for those who like detached living heads, the resurrection drug totally works on severed heads.