The first katana was forged by Jesus himself (out of a meteor) and he used it to destroy the Roman empire in a single swing. A typical, average katana can cut through 30 cm of titanium. During the full moon it can shoot lasers and produce rainbows out of it's tip. In fact, samurai in the 16th century were well known to deflect AK-47 fire with just their swords.

Here's a comment I know you'll "love".... $WAG