Blind Weaponmaster

"A J-Jedi doesn't... need eyes!"

—Luke Skywalker, immediately after being blinded, Vader's Quest.

They hold their sword (or other Weapon of Choice) like they know what they're doing, but since they're completely without sight surely they aren't that dangerous...? Wrong. The Blind Weaponmaster is one of the most deadly adversaries a character can face. In possession of supernatural senses born from blindness or just Badass Normal enough to compensate for their loss with other natural senses, the Blind Weaponmaster will surprise any overconfident character and make a hero push their skill to its limits.

A subtrope of Handicapped Badass.

Examples of Blind Weaponmaster include:

Anime and Manga

Irako Seigen in Shigurui.
Usui from Rurouni Kenshin, literally known as "The Blind Sword".
In Samurai Champloo Sara turns out to be an extremely skilled ninja.
One of the Quirky Miniboss Squad in Ninja Scroll is a blind swordmaster. He can feel out the location of the sun and reflect it off his sword as a blinder, turning the tables on his seeing enemy.
Shiryuu in a part of Saint Seiya.
Mamoru from Until Death Do Us Part. A master of the katana to the point that he uses it as his only weapon IN ACTUAL MILITARY COMBAT and owns everyone's asses. And yes, he's blind without the special glasses that Igawa made which show him where objects are as wire frames on a perspective grid. He's almost just as good without them, though.
Mousse in Ranma 1/2, not blind per se, but so short sighted that even with coke-bottle glasses he cannot distinguish between people and objects, fights with a range of deadly bladed weapons. Interestingly enough, while he's been known to mistake a bicycle for a long-haired Chinese girl, he has absolutely no problem fighting even deadly, fast-moving adversaries in the night and without his glasses.
In Pandora Hearts Xerxes Break eventually loses his eyesight. Doesn't stop him from being (arguably) the most Badass character in the entire manga/anime.
Another blind swordsman is Kaname Tousen from Bleach up until his hollow transformation. Ironically, it was gaining sight that led to his downfall.

Comic Book

The title character in Daredevil.
- Also his teacher, Stick.
  - And Stick's teacher, Master Izo ("Master" seems to be part of his name, he's that badass).
Zato Ino, "The Blind Swordspig", in Usagi Yojimbo, can "see" things thanks to his sense of smell.
In Old Man Logan, an elderly Hawkeye has lost his sight. However, as long as he can hear his target, his aim is just as deadly as ever.
Cyclops of the X-Men has two options when he loses his glasses: Keep his eyes open and kill everything in sight, or keep them shut and beat the living hell out of his opponents while counting his footsteps so he can find his way back to where his glasses landed.
In Vader's Quest, Luke is blinded, temporarily, but that doesn't slow him down, at least at first - a dozen or so people immediately try to kill him, and he beats them all without killing any of them. It's only later, when he's not fighting, that he has trouble.
King Snake, in the Batman family of comics, was blinded by gunfire at an early age, but became one of the best martial artists in the 'verse in spite of it. He's so good that on one occasion where his sight was restored, it actually threw him off his game enough that Tim Drake's Robin could hold his own against him.
The Blind Master from Marvel Comics G.I. Joe series.

Film

the titular Eli, from The Book of Eli.
Ichi from Zatoichi.
In Scent of a Woman blind retired Army Ranger Lieutenant Colonel Frank Slade shows his nephew Randy that you don't insult Charlie.
Ray Charles in The Blues Brothers. Fires a couple of warning shots at a would-be guitar thief.
Rutger Hauer in Blind Fury.
The titular Master of the Flying Guillotine, who's also an Improbable Weapon User.
Parodied in Dinner for Schmucks, where one of the eponymous "schmucks" fancies himself a blind Master Swordsman. He isn't.

Literature

Drizzt in The Dark Elf Trilogy meets and learns from one.
In Ea Cycle Atara becomes a combination of this and Blind Seer after she gets blinded by the Big Bad.
In Neuromancer, Hideo the ninja is this, though not actually blinded until very late in the story.
Maestro Killian, the trainer of Cursors in the Codex Alera book Academ's Fury. He compensates for his blindness through his furycrafting.
Two of them in Swordspoint. One of them Richard is regretfully forced to kill, the other one is Richard. Later in life, anyway.

Live Action TV

Blind assassin girl on Angel "Blind Faith". She made herself blind living in a cave, but her infrared ability will still let her kick your ass.
Subverted by an episode of Star Trek: The Next Generation where Worf blindfolds a martial arts student as part of a test and tells her to anticipate his attacks. He kicks her ass until she quits, saying that the test is unfair. Worf admits of course you'll lose a fight if you're blind. The real test was getting the nerve to say that to his face.

Music

The Knight in Leslie Fish's "Cripple's Shield Wall." He cannot see, and must know his ground in a fight, but that's compensated for, he is scary good with the sword and unhampered by "dark, fog, or rain"

Video Games

Haborym, from Tactics Ogre.
Kenshi from Mortal Kombat: Deadly Alliance.
Visas Marr from Knights of the Old Republic II; since the Miraluka are all blind but "see" with the Force, any Miraluka could be this.
- Also, Kreia has let her eyes "atrophy from dis-use", using The Force to see instead. This does not limit her combat abilities.
In the World of Warcraft universe, Illidan Stormrage started out as this.
- Actually, he started out as a magic user. The swords came later.
Riku spends the majority of Kingdom Hearts II (and an uncertain amount of time between Chain Of Memories and II) wearing a blindfold. He wore it for so long, he forgot he was wearing it!
The Asura subclass of the Slayer from Dungeon Fighter Online. Purchases powerful Sword Beam spells by selling his eyes to a demon parasite in his left arm.
Augus from Asura's Wrath is apparently one of these. Albeit hard to notice at first because the demigods tend to have white glowing eyes regardless, Asura's threat to "Rip out those blind eyes" makes it obvious.

Web Comics

Homestuck's Terezi is very handy with her cane. Though she's not entirely blind (she can see synaesthetically via smell and taste).

Western Animation

Avatar: The Last Airbender: Toph is blind and fights using the power of earthbending to 'see' via the vibrations she feels through her feet.
Subverted in The Boondocks with Stinkmeaner. In his first confrontation with granddad he kicked Robert's butt and Huey assumes it's because of this trope. Turns out he just got lucky and wasn't a good fighter at all.
Teenage Mutant Ninja Turtles: In the 2003 series, there is one episode where Donatello is sent to a Bad Future where the Shredder has enslaved the earth. This future Leonardo is heavily-scarred and wears dark, round shades instead of his mask, implying that he is blind. It doesn't stop him from being an excellent swordsman and nearly killing Karai.
In Bad Future episode of Gargoyles, Broadway is blind but can "see" using an echolocation collar invented by Lexington, allowing him to fight.

Real Life

This guy, a champion of blind judo who beat up a mugger.
One of Jorden Weir's 5 People Whose Major Disabilities Only Made Them Stronger is a blind sharpshooter by the name of Jim Miekka.