Getting bored, I spawned an ardvark by the lava in arena, turned it into a wambler, and punted it at the lava, it skipped across the lava for about 10 squares (like a tossed stone) before finally sinking and melting, but this was taking forever, so i proceeded to kick it around under lava for a while, got tired of this, and pinched its head off.
(it probably took so long to die because of the fact that this guy has speed of 10k by default (above or below water) meaning i got like 100 turns before they got even one, and thus i was moving so fast it took forever (from my perspective) for them to die)
I did that on only one, and wondered how it survived the impact, and proceeded to beat the "pudge" out of it. I have determined that they can't die from blunt damage, as they have no organs other than this "pudge" stuff, which doesn't seem to be very vital, though it will bruise, (one hit to any part of them by me makes it blue light blue) and their limbs dont seem to go flying off when i kick them with the force of eight freight trains, probably because they are so small that the force just sends THEM flying, rather than part of them.
Additionally, after checking the wiki, I found out that that message happens when enough blunt force to cause instant death is applied to the lower body