Und smashing skullen und...
The wicked thing about those WWI trench knives is that you could inflict serious damage in so many ways. You have a double-edged knife that can stab or slash from either direction. You have a good old set of brass knuckles for a grip, making it hard to knock out of your hand and capable of breaking someone's jaw. And, for good measure, there's the spike on the hilt for cracking someone's skull.
There are some sick minded SOBs who design things like this.