Gáe Bulg

Boomerang shrapnel spear SEEMS LEGIT

And in the Fate series (Fate/Stay Night, etc), Gae Bulg is a spear that would manipulate causality to always pierce the heart of the victim, no matter what angle the spear is thrust at.

A different take on the same folklore but still crazy powerful.

You think THAT'S crazy? Try Caladbolg on for size. "It was said to be a two-handed sword that made a circle like an arc of rainbow when swung, and to have the power to slice the tops off hills and slaughter an entire army."

So let's recap: A zweihander that shoots rainbows, shaves hilltops like blades of grass and SLAUGHTERS ENTIRE ARMIES.

I rest my case.

Also notable weapons include:

Thuận Thiên (heaven's will) -a Vietnamese sword that made the user grow tremendously tall and strong

Dyrnwyn (white hilt) -a Welsh sword that would blaze with intense heat when wielded by a hero

Durendal -a French sword that was literally indestructible and was used on multiple occasions to cut through large boulders or mountains

Crocea Mors -a Latin sword that insta-killed anyone it hit

Dáinsleif- a Nordic blade that required a man to die any time it was drawn, and whose slightest slice would result in a cut that would never heal

probably others that i'm forgetting

This is fun