What's more simple than a bow? A bullet. Bullets just have to be shot out of a gun and somebody dies. Bows you have to load with an arrow and pull it back and aim, yuck. Bullets are the new bows, people.
ひ, はず, たま
If you want to shoot bullets, you need to do it at dawn (だん). Back in the old days, it wasn't bright enough to shoot arrows at dawn, but you can shoot bullets at dawn because they're simpler to use!