The Knight

The Knight (騎士 ザ・ナイト Za Naito) is a Holder Type magic and style of Requip magic used by Erza Scarlet. This magic allows her to store weapons and armors in pocket dimensions and summon them during battle, which gives her a high level of flexibility in combat. Erza stated that there is a limit to how much the pocket dimension can store and leaves some of her armors in her room in Fairy Hills.

Armors

 * Heart Kreuz Armor: Made by Heart Kreuz, this is Erza's casual armor, which she is mostly seen wearing until it was modified. She sometimes only requips her swords, but doesn't change this armor.
 * Heavens Wheel Armor (天輪の鎧 Tenrin no Yoroi): This armor is used to face multiple opponents. Plated armor covers her chest, with a large metal flower over it, and she wears a large billowing skirt that has metal plating in the upper area. Her stomach and neck are uncovered, and she has large metal wings that appear to be made of individual blades, as well as a wing-like headpiece. This armor has the ability to launch weapons at her opponent. In this armor, Erza is able to summon a large amount of swords (roughly more than 200 in the anime while trying to destroy the Thunder Palace). One of the special attacks that can be utilized by her Heaven's Wheel Armor is "Blumenblatt". The spell casts a barage of swords towards the target and gives an electrocution at the enemy as the swords settle on the opponent.
 * Black Wing Armor (黒羽の鎧 Kureha no Yoroi): This armor increases the destructive power in Erza's attacks. It is black with silver trim, and sports batlike wings (later feathery in the manga). While wearing this armor, she only uses one sword. This form first appeared when fighting the demon of the Lullaby. While wearing this armor, she is able to glide through the air.
 * Flame Empress Armor (炎帝の鎧 Entei no Yoroi): This armor lowers the destructive power of flame attacks by 50%. In the anime, she's also show using fire magic while equipped with this armor. In this form, she has no armor on her shoulders and more on her limbs, the boots closely resembles dragon feet. This form first appears during her brief duel against Natsu.
 * The Giant's Armor (巨人の鎧 Kyojin no Yoroi): A full body, yellow armor, with large shoulders, and fur trimmings and a black cross on the chest. In the anime, the right arm of the armor is considerably bulkier than the left. In this armor, Erza is able to increase the strength of her throwing power. First shown in Galuna Island arc to send a spear flying to "destroy" the moon.
 * Adamantine Armor (金剛の鎧 Kongō no Yoroi): This armor is the ultimate, high-level defensive stance. In the anime it features two shields on the arms, which can be brought together to generate a large magical barrier. In this armor, Erza is able to withstand the magic fired by the Phantom Lord's Jupiter Cannon.
 * Purgatory Armor (煉獄の鎧 Rengoku no Yoroi): Erza's second most powerful armor (second to her new Armadura Fairy), and according to her "None has seen this armor and lived to tell the tale, witness it and despair." Its true power is not seen as it was destroyed almost instantly by Ikaruga. She then uses this armor in the anime episode "Wizard of Fairy Tail" wherein she attacks the center of the Dragonoid.
 * Lightning Empress Armor (雷帝の鎧 Raitei no Yoroi): This armor lowers the attack damage of all thunder attacks aimed at Erza. Laxus stated that it wasn't enough to stand his thunder magic; however, the single attack aimed at Erza in the anime did no damage to her. In the anime Erza also states it is not just for defense, as she can now fire blue lightning attacks towards her foes.
 * Flight Armor (飛翔の鎧 Hishou no Yoroi): An armor that increases Erza's speed that was used to fight Cobra and her Counterpart. It has a leopard-patterned chestplate and shoulder guard, and a cloth from her waist down. There are also a pair of leopard ears on her head, and a bushy tail.
 * Robe of Yūen (悠遠の衣 Yūen no Koromo): An armor that is more of a beautiful kimono equipped with a bisento. This armor has elastic properties which prevented Midnight's Reflector magic from binding her.
 * Morning Star Armor (明星の鎧 Myoujou no Yoroi): An armor with a similar design to the Heavens Wheel Armor, sporting fishnet leggings. Able to fire off magic blasts.
 * Armadura Fairy (妖精の鎧 Yousei no Yoroi): The strongest armor as declared by her counterpart, Erza Knightwalker. This armor has the name of her guild to symbolize her pride of being a member of Fairy Tail. The attack of this armor was strong enough to break Knightwalker's strongest spear, Ravelt, and shatter an entire island, although breaking in the process.
 * Sea Empress Armor (海王の鎧 Kaiō no Yoroi): According to Lisanna, this armor nullifies water attacks. It has been shown withstanding Juvia's water attacks.