Sightblinder is also called the Sword of Stealth, and less commonly, the Sword of Deception. It bears a stylized human eye engraved in white upon its hilt.
Sightblinder's verse in The Song of Swords describes its power as follows:
- The Sword of Stealth is given to
- One lowly and despised.
- Sightblinder's gifts: his eyes are keen
- His nature is disguised.
Sightblinder's powers are twofold. First, it alters the appearance of its possessor. This is not via a traditional cloaking device or holographic projection, but it alters how outside agents perceive the person carrying the Sword of Stealth. When a person looks at someone holding Sightblinder, they believe they are looking at either someone they love and trust implicitly, or someone they fear.
The illusion is complete, regardless of how perceptive or skilled in magic the target may be. One may see Sightblinder as a parent, sibling, lover, god, or leader. The effect is so convincing that the target has trouble doubting the identity of the person they are looking at, even if it is changing from moment to moment. Sightblinder will disguise its bearer's voice if required. Sightblinder disguises itself as well, appearing as a cane, a scepter, another Sword, or even as nothing at all, depending on what would enhance the illusion.
The consistency of the illusion varies. In some situations involving multiple targets, every person will see something different. At other times, all present see the same thing. The illusion may switch from a person one fears to a person one loves and back again over the space of a single encounter (as when a dragon flew off, impaled with the blade), or it may remain the same over a long period of time (in the case of Mark impersonating a senior officer of the Dark King over a period of several days and with a large number of people). The series never establishes how an image is kept consistent—though it appears that the intelligence or consistency of purpose of the wielder plays a role.
In practice, the effect is similar to the Mindsword in that the target will obey the wielder. Unlike the Mindsword, the subject will not totally disregard their base inhibitions and are unlikely to throw their life away for the illusion, unless that is what they are naturally inclined to do.
A drawback to use of the Sword is that it makes sneaking around impossible. When one appears as a fearsome god, demon, or an intimate relation, they do not easily escape notice. Indeed, the Sword is best used boldly.
A secondary effect of Sightblinder is that it enhances the perceptions of the person carrying it. Their eyesight and hearing are supernaturally keen. It also allows its bearer to see through other illusionary magic and effects, no matter what the origin or strength. It offers some protection from the Mindsword by allowing its user to see the true nature of the other Sword's possessor. Sightblinder's bearer intuitively can tell when a person is being honest or deceitful.
As powerful as Sightblinder's illusions are, it cannot fool the one who carries Shieldbreaker. Farslayer is not fooled by the illusion. Some characters in the series speculated that Doomgiver would be able to reverse the effects of Sightblinder onto its own wielder, but this has not been seen in practice.
Read more about this topic: Twelve Swords Of Power