557 – I was assuming you were going with the classical interpretation of rodef and nirdaf. How can one 2 dimensional point by a rodef? Furthermore, a nirdaf is allowed to kill a rodef. Assuming they were both people, moving at sprinting pace, a gun would have worked for either of them.
If they’re in a “closed” two dimensional circle (I guess this can be imagined like a circular pair of train tracks), and they both move at light speed, then they can’t catch eachother unless one of them breaks the circle…. Or if the rodef blocks the circle with some object and then corners the nirdaf on it.. your rules aren’t very clear.