Backstabbing? I have no clue what the term for this is.

[RPGenie]

So after spending some time throwing fists at the local fauna that dot the wilderness, I noticed that sometimes, despite having 50 some odd UA, an ant swarm would smack the everloving bejeebus out of me, breaking through a 100% defense and stunning me in a blow that drained the bar and blew through all my damage reduction.

I just normally wrote this off as a "critcal hit" for lack of a better term. Then I noticed I could do the same to a critter whenever it was running away from me in melee.

This seems to be a "backstab" for lack of a better term to call it. My question is this. Do they happen whenever someone strikes you squarely from behind? Or does this ONLY happen whenever you're running away from someone engaged in combat with you and then they strike you from behind?

It'd be disturbing to see a level 1 UA peasant hokuto no ken his way through a fully armored warrior's steel plate and reduce his defense bar to 0% merely because they snuck up behind while he was occupied.

[Zamte]

Hitting a moving target always bypasses it's defense bar in melee (as in close range, not only with weapons) combat. That's why, assuming you can keep up with it, it's always pretty easy to finish off a wounded animal.

[RPGenie]

Thank you very much! I'd checked around the wiki some, but I couldn't find anything relevant. I'll be a little more judicious with repositioning myself in combat. It can be a painful mistake when a level 9 fox gnaws your leg off because you wanted to make it run towards the heathland and not the forest.