The backstab modifier is great, but in my experience there's very little opportunities to use it. It's fun to use on a lox, but make sure you're able to get away from his buddies in time if you need to use it.

Other than having fun with loxes, what would you use it on? It's overkill for most things. A simple parry followed by a triple combo will take down most anything that's anywhere near your league.

The key is making sure you have enough stamina to complete the combo (if necessary) and/or ensuring that you're not fighting multiple stronger enemies, since you can only fight one at a time. Since it doesn't take much stamina, the stamina part is fairly easy.

That reminds me. I have a game that's waiting for me to try a backstab on a 2* berzerker with skoll and hati. That should be fun!