Honorblade

The swords of the Heralds — the templates on which living spren-Blades are based. Syl explains to Kaladin on the broken Plains that Honor gave these to men, and the men who carried them gained powers; spren figured out what He had done and imitated it, which is what she and Pattern and the rest of the bonded spren now are — bits of His power, like the Blades themselves. Any man who holds an Honorblade becomes a Windrunner (or the equivalent of whichever order the Blade was a Herald of) without the checks a spren bond requires; the weapon also burns through Stormlight at dangerous rates. Szeth carried one across the world as the Assassin in White; Kaladin takes it from his body after killing him on the stormwall, and the Shin are confirmed by Syl to hold the others. SA:WoR:Ch 87

A type of mystic sword wielded by the Heralds. Capable of being driven hilt-deep into solid stone; when stabbed into rock it leaves the blade fixed there as if cast. SA:WoK:Prelude