In my opinion, this is already a pretty cool bonus, but I can consider adding something else. Like increasing the chance of blocking or increasing the gradual blood loss effect with "gutting." That's the most obvious thing.
It makes sense to change the AoE attack. That is, make it so that double damage is dealt to the target cell, and normal damage is dealt to the cells to the right and left of it (previously: normal damage was dealt to the right).