Iron Knuckle

Iron Knuckles, known as Ironknuckle in  and called Ironnack in the The Official Nintendo Player's Guide entry for The Adventure of Link, are a recurring enemy in.

Characteristics
Iron Knuckles are large, heavily armored knights, equipped with swords or axes capable of dealing immense damage. Though quite similar to Darknuts, Iron Knuckles are less common across the series, and usually play the role of stoic guardians as opposed to the more aggressive behavior of a Darknut. The main difference, however, is that they do not share a Darknut's traditional weakness to attacks from behind. These foes are dueling elites, incorporating much of the same swordplay technique Link does during battle to great effect. These knights are also known for their unmatched defensive capabilities and long vitality. In their debut, The Adventure of Link, they predominantly appear in the temple dungeons where it is said they were "iron warriors" chosen by the King of Hyrule. They fight with both sword and shield, and appear in three varieties of increasing strength: orange, red, and blue, with the blue Iron Knuckles being capable of shooting Sword Beams (referred to as knives in the NES Game Atlas).

Iron Knuckles later appeared as mini-bosses in and, in the former appearing as a facet of the plot at the Spirit Temple, and in the latter as guardians that appear predominantly under the Ikana Graveyard, protecting tombs. In Ocarina of Time, several Iron Knuckles are encountered throughout the Spirit Temple. Twinrova had also kidnapped Nabooru in the past, the Sage of Spirit, and held her in the Spirit Temple. In the future, when Link confronts Twinrova for the first time, they send an Iron Knuckle, which turns out to be a brainwashed Nabooru under its armor. Even after he defeats her and regains her consciousness, she is again captured by Twinrova. In Majora's Mask, there are only three Iron Knuckles: two are beneath the Ikana Graveyard on the First and Second Day, respectively. One is guarding the resting place of Flat and the other is guarding a Piece of Heart. The third is in the Link Dungeon in the hide and seek game played by Link while in his Hylian form. Also in Majora's Mask, gold Iron Knuckle armor can be seen on display in the Curiosity Shop. This armor is actually used as a peep hole from the back room where Kafei spies on the Curiosity Shop's dealings. Interestingly, this armor wields a sword instead of an ax, similar to the Iron Knuckles of The Adventure of Link.

The Iron Knuckles of Ocarina of Time and Majora's Mask were distinguished from Darknuts of previous games by their use of huge axes, capable of taking four hearts from Link at every swing, making them one of the strongest recurring enemies in the games. Their grand size and armor coverage also meant they took many hits to defeat, but their slow attacks and recovery are their weakness. Like in The Adventure of Link, they also come in varying strengths and colors. Nabooru's Iron Knuckle armor in Ocarina of Time in particular is larger and has more extravagant armor. Her's is also unique in that her armor falls away and harmlessly reveals her upon defeat.

Strategy-wise, Iron Knuckles in The Adventure of Link are experts at defensive strategy, using a shield they constantly move up or down to block Link's attacks while also attacking high and low. Link must also focus on defense and watch the swing of its sword and block accordingly while looking for an opening. He can use the Shield Spell to protect himself when fighting them. It is also possible for Link to jump and perform a Down Thrust at its head to inflict damage.

In Ocarina of Time and Majora's Mask, they are particularly weak to Jump Attacks while they recover from failed ax strikes. The armor of the Iron Knuckle can be damaged, providing two stages to every battle. While wearing armor, they are slow and impervious to all attacks save for sword swings and Bombs. Once enough armor is removed, they become enraged and move quicker, but are now weak to Arrows, opening up the opportunity for a successful long-range strategy. Despite their similarity to Darknuts, it is not recommended to attack an Iron Knuckle from behind, as they can perform a fast, deadly spinning attack to counter such a strategy. Nayru's Love is particularly useful when fighting Iron Knuckles due to the extensive damage they cause.

Rebonack
In The Adventure of Link, a blue Iron Knuckle called Rebonack is the Boss of the Island Palace. This boss is also sometimes referred to as "The Guardian Ironknuckle" or simply "Ironknuckle". It rides a levitating steel horse and wields a lance, and charges at Link at high speed. Two more Rebonacks appear as mini-bosses in the Three-Eye Rock Palace, one of which guards the chamber containing the Cross and the second appearing before the pit that leads to the boss, Barba. While riding on the steel horse, they are only vulnerable to the Down Thrust, but once having taken enough damage, they will dismount and fight Link as a regular blue Iron Knuckle.

The Wand of Gamelon
In, an Iron Knuckle appears as a minion of Ganon and as the second boss. He is located in Tykogi Tower.

He had captured the residents of Sakado, including Mayor Cravendish and Harbanno the baker, and imprisoned them in Tykogi Tower. After freeing Harbanno, Zelda fights and defeats Iron Knuckle atop the tower, who then breaks apart and reveals a beating Life Heart. Two Armos witness his death and quickly decide to leave. Zelda then rescues Mayor Cravendish shortly after.

Iron Knuckle's only weakness is the Power Glove, which will defeat him in a single strike. Zelda, however, must also be careful not to get too close, as this gives him a chance to strike back.

This is the only instance of an Iron Knuckle appearing in the same game as the similarly armored warriors known as Darknuts.

Theory
The fact that other Iron Knuckles dissolve completely when defeated in Ocarina of Time and Majora's Mask lead to believe that they are animated by magic. However, carefully positioning the game camera through them reveals a Gerudo with a vacant stare similar to Nabooru. This is likely because the scene that follows the defeat of Nabooru as a Iron Knuckle shows her armor falling off, with a stunned expression on her face, and all Iron Knuckles use the same body model with slightly different outer armor. Though this head was removed from, their body type is still present as it was in Ocarina of Time and Majora's Mask. In fact, the Gerudo body is more visible, allowing to clearly see the chest of a Gerudo when the armor falls off, something that seems to be deliberately done as the head was removed from the model. As a result, some believe that all Iron Knuckles are actually heavily-armored Gerudo brainwashed by Twinrova. However, as this model is not readily visible to Link and requires careful camera manipulation to view, this may be a graphical oversight. The same model is reused in Majora's Mask with the same glitch achievable.

Trivia

 * In the Famicom Disk System version of The Adventure of Link, blue Iron Knuckles' Sword Beams flash and will disappear when blocked, much like Link's own, but in the NES version they do not flash and bounce off of Link's shield.
 * Iron Knuckles previously held the record for the highest damage output in a single attack of any regular enemy in a Zelda game, dealing four hearts of damage in Ocarina of Time and Majora's Mask, as well as eight hearts in . This record was lost to Shadow Link and Gramps in, who can deal 32 hearts worth of damage in Hero Mode.
 * Nabooru's Iron Knuckle armor in Ocarina of Time does not start out with a weapon. Instead, it summons an ax from thin air by snapping its fingers.
 * Onox, the main antagonist of, highly resembles the appearance of an Iron Knuckle. The only considerable difference is that Onox wields a Ball and Chain, while Iron Knuckles tend to use swords or axes.
 * Iron Knuckles from Ocarina of Time and Majora's Mask wear a cloth tunic bearing Gerudo patterns, similar to those seen on Ganondorf's and Twinrova's clothing.