Till death or at least one of them cannot move anymore.
Peak Widow vs her opponnent is also at his / her peak. Widow has her most commonly used sword. Her enemy gets his most common weapons.
Location: inside the London Tower. Everything in the tower is fireproof and the walls cannot be damaged, nor the floor and ceiling.
Starting in different rooms 40 meters from one another. They go at each other. No one is playing hide and seek.
vs