In the final round, bladesmiths must forge one of the most iconic weapons from history; the Japanese Katana.

Four bladesmiths must forge a weapon using only reclaimed metal.

The bladesmiths must transform a steel "train spring" into a weapon.

For this week's challenge the competitors create their signature blade by using the Hada technique--a traditional process that involves forging multiple layers of steel together.

The forge heats up as our four bladesmiths struggle to create a special Japanese hardening technique on their signature blades.

The forge heats up as the bladesmiths must use an age-old technique to create their signature weapons.

Four bladesmiths heat, hammer and grind their way through a first round challenge where they must transform a steel ball bearing into a fully functional weapon.

The bladesmiths must forge a signature weapon using everyday steel objects like ball bearings and shovels.