: Compared to typical iron or pattern-welded blades of the Viking Age, Ulfberht swords were incredibly strong, flexible, and sharp, allowing them to slice through mail armor without shattering.

: On collector forums like the Nihonto Message Board , it is often used for modern Chinese fakes that mimic Japanese signatures but lack the correct historical construction.

The phrase is also popular in modern gaming and fiction to describe "illegal" or overpowered weapons: