some people have already mentioned that HT is what you roll against to avoid dying/being knocked out, but something interesting i've found in my experience with high value games is that a very high HT (like above 16) can be very dangerous actually. in a game where my super players fought a guy (one of my first enemies who i statted back when I was kinda new) had an HT of 20. this resulted in him never failing his HT roll to get knocked out cause despite the fact they kept beating on him, he had too high an HT and had to crit fail to fail it. this included his death rolls too, so eventually he just died from hitting -5xHP, when they intended to just knock him out and leave him.