Swords are also hard to control with a mouse and keyboard.

Imagine yourself surrounded by a transparent sphere, on which you can paint a point and a line. Where on the sword is that point? How does the point/sword travel along a line?

This is not easy to solve. What happens if you shift your perspective after a sword attack is drawn? Can you amplify it by looking away? Can you arrest the motion, by looking towards the executed sword motion.