This hit can be fatal, repeat FATAL, because of how the multiple hits score increasingly dangerous critical hits. With 4 adv, you can score 5 hits. These hits are handled as separate hits, which can cause separate crits.
If the first hit (and with 10 damage, is likely, but not guaranteed) exceeds your wound threshold, it causes a critical injury. Then each subsequent you cause four more hits, at +10, +20, +30, and +40.
Okay, so I'm… a hit or two shy? Regardless, the demonstration illustrates my point, that these completely plausible, if not frequent, roll results will cause players to get absolutely f***ed! A player with most of their wound and one or two minor critical injuries from earlier in the combat could die, and will certainly be in a very, very bad way.
This is why I think AF's current state is broken.
-WJL