Instant Armor

Powered Armor is nice, but also kind of clunky - getting through narrow passages can be a pain, and getting out of it in a hurry 'cuz you need to go to the loo is quite troublesome as well. Wouldn't it be much nicer if you could just create a suit out of thin air - or, alternately, out of whatever raw-materials happen to be handy - whenever you need one? Well, if you've got Psychic Powers or Functional Magic, or just some really nifty gadgets, you can!

Can range in size from Powered Armor to Humongous Mecha. When used by villains, it's generally a form of One-Winged Angel. Note that we're not talking MacGyvered Powered Armor here - rather, the armor is propelled and assembled by supernatural power of some sort, or teleported in/assembled on the spot by Nanomachines. As a rule of thumb, if it takes more than a couple of minutes to assemble, it does not belong here.

Collapsible Helmet is a more specific Sub-Trope where only the helmet appears/ disappears.

Compare/contrast Henshin Hero, Elemental Armor, Elemental Barrier, and Wreathed in Flames.

Anime and Manga

 * Sensui from Yu Yu Hakusho can use his Holy Light Energy to create two special sets of armor.
 * The protagonist in S-Cry-ed's Alter power develops like this, initially covering just his arm, but later progressing to the right half of his torso, then full body armor.
 * As well as  - any Alloy-type Alter user does this to some extent, and it is implied by   that all Alter powers must become Alloy-type to unlock their maximum potential.
 * Not so much covering as converting - the arm is actually transformed. (When he undergoes the whole body conversion, his legs are actually thinner than when untransformed, and in the original Transformation Sequence we see his arm splitting into three segments.)
 * Hey you notice how he's always wearing a glove and long sleeves? On the few instances when he's not, you can see lines across his hand and arm. As the armor grows across him on varying levels, those lines appear where he's transformed. Turns out it's not just stylistic, those are scars left from where his own body was torn apart by his Altar power and reconstructed into armor. It's to the point that, after unlocking his second level, his one eye only opens when manifesting the armor... It was heavily damaged right before the first manifestation, and now it appears to potentially be part of the manifestation.
 * The Barrier Jackets from Magical Girl Lyrical Nanoha are conjured out of thin air and can take more beating than a main battle tank. Sure, they don't look that way in some cases but Signum's, for example, both looks and functions just right. Presumably as a result of being able to be ready for battle in an instant, Bureau mages tend to wear their "dress" uniform virtually all the time outside combat when they're on duty.
 * It is noted that the more Stripperiffic the Barrier Jackets are, the less protection is given. Fate's Sonic Form Barrier Jackets do precisely nothing in the way of protection, they just enhance her speed. As Signum comments, if Fate gets hit, she'll die.
 * The many various Fragile Speedsters would like to point out that it's a case of "if" she gets hit.
 * The Homonculus Greed from Fullmetal Alchemist can use the carbon in his body to generate a Nigh Invulnerable second skin which he calls "The Ultimate Shield". Greed usually only armors up his arms (giving him claws in the process) and whatever specific body part is about to be hit, because full-body armor makes his face ugly.
 * Saber and Gilgamesh/Archer in Fate/stay night and Fate/Zero are both capable of this. Saber's is essentially made entirely of her magic energy. Gilgamesh presumably either does the same or simply pulls it through Gate of Babylon.
 * The Mimetic Beasts of Godannar, who are small, alien organisms who create huge bodies for themselves out of available materials - whether that is rocks, people, or a space-shuttle...
 * Referred to as Ex-Quipping in Fairy Tail. Instant Armor is Erza's particular specialty, and she sure has a hell of a lot of armors.
 * The titular Infinite Stratos, are powered exoskeletons that teleport onto/around the user, that are summoned via wrist band a la Power Rangers. The user has the option of just summoning the right gauntlet of their machine, a function that is used, more often than not, as a gag like a Hyperspace Mallet.
 * Noteably, only the 'personalized' IS-units have this function. The mass-produced Red Shirt models are just run-off-the-mill Powered Armor.
 * The Mushi of Mushi-Uta are mostly Mons, but the one belonging to the main character Kakkouisa 'fusion' type. In the beginning, it just merges with his arm and Hand Cannon to form an Arm Cannon, but with time, it grows bigger and covers more - at the end, it's basically a suit of Chitinous armor that he can call up at any time. (Unfortunately, it sort of looks - and acts - like Cthulhu Tech...)
 * The Robes from Mai-Otome. Once their receive authorisation from their Masters an Otome can summon their Robe within the space of a few seconds. The Five Columns don't even have to worry about authorisation.
 * The Bio-Booster Armour from Guyver. The live-action movies had them erupt from bumps on the protagonists neck from some form of Hammerspace. The anime and manga just directly summons it from Hammerspace with a mini Sphere of Destruction that vaporises any enemy foolish enough to get close to you while transforming.
 * One of the contractors in the second season of Darker than Black can instantly assemble improvised mecha around himself out of whatever materials happen to be nearby.
 * Mahou Sensei Negima
 * Jack Rakan can summon arm and leg armor via his artifact. And seemingly move it telekinetically, as
 * After becoming an Ariadne Knight, Yue can summon a set of full armor too.
 * Yasutora "Chad" Sado in Bleach eventually is able to summon "Giant's Right Arm", and later "Devil's Left Arm", granting Super Strength and energy attacks. Once he realizes the true nature of the former and unlocks its true form in the middle of his battle with Gantenbaine, it also serves as a way of defending against attacks.
 * Lots of characters can do this in Zatch Bell. The strongest armour spell seen in the manga can even shapeshift and grants jets.
 * In Heroic Age, the Silver Tribe can assemble their Full Hedron spaceships out of apparently nothing in under a minute. Couple this with their ability to survive at least a few minutes in vacuum and their ability to teleport, it means that blowing up a Hedron is a minor setback at most unless you manage to kill the Silver Tribesman himself (and considering the power of their personal Hedron Shields, this is easier said than done). All of this is accomplished through extremely advanced technology and Psychic Powers rather than anything explicitly supernatural, though.
 * One Piece
 * Mr. 3 can create a suit of wax armor for himself that's harder than steel but melts when exposed to fire.
 * Wanze's Mens Formal Suit (a suit of armor made of ramen noodles) borders on parodying this trope.
 * Also, Rayleigh describes Haki as this, only invisible.
 * Saint Seiya is all about this trope. It used to happen at least Once Per Episode until the later sagas where they always had their armors on.
 * One of the Black Phantom villains in Zettai Karen Children has the ability to spontaneously create Humongous Mecha suits for himself, by using a combination of telekinesis and illusions. The suits are ACTUALLY just a number of handy vehicles and random bits of scenery suspended in the air and moved with TK, but his illusion-projection abilities makes it look—and act—like a classic mecha.
 * Coco from Toriko can instantly coat himself with the poison in his body.
 * Believe it or not this trope is invoked a few times in the Metroid manga, that's right Samus actually could hide her Power Armor in very small place and summon it whenever she wanted.
 * The mysterious Henshin Hero, Brave, of Ichiban Ushiro no Dai Maou, is empowered by a rather sleek suit of Magitek Powered Armor, which he can summon from another dimension with his Transformation Trinket wristband.
 * Armor-type Over Souls in Shaman King are these.

Comics -- Books

 * Magneto of the Marvel Universe has been known to do this, from time to time, using his metal-control. Ranging from reconstructing his own broken armor from nearby junk, to forging himself into a gigantic steel titan! At one point, he disassembled his suit, sitting on a chair nearby, into sand-sized grains and re-formed it around himself, in seconds.
 * Another X-Men example: Armor can create magic armour around her body. (Well, DUH...) She would mockingly acknowledge the "duh" factor by wondering what if she called Wolverine, well, "Claw"... or "Stench"...
 * The latest Blue Beetle, Jaime Reyes, has this power thanks to the Scarab, an incredibly powerful piece of alien wartech that implanted itself in his body. Just don't ask where the mass of the suit comes from. Dan Garrett, the first Blue Beetle, could also use the Scarab to call up a suit of armor (although since the Scarab was damaged at the time, it was nowhere near what it could do for Jaime).
 * Iron Man
 * The Extremis armor can do something like this. All the pieces are self propelled and can assemble around Tony in a matter of seconds. The Extremis armor however was actually constructed of some kind of techno virus that actually stored the inner layers of his armor inside Tony's body. It also gave him a Healing Factor and technopathic powers. However it also caused Tony's body to be affected by hacks and viruses to the armor as well.
 * A lot of Tony's older model suits could do much the same—stored in cases little larger than a briefcase (or, in some cases, actually in a briefcase) he could go from Tony to Iron Man in seconds. And he could even summon the armour from a distance, which would fly over to him before enrobing him.
 * His newest armour, the Bleeding Edge Armour, is stored in its entirety within his body.
 * Towards the end of the Reality Check semi-manga, Mr Bunwah is carrying one of these for the heroine.
 * The Engineer (of Authority fame) replaced her blood with nine pints of polymorphic metal. She generally extrudes enough of it to make a gleaming silver bodysuit.
 * Samantha of ClanDestine can generate "ectoplasmic" armor and swords which are impervious to anything short of Wolverine's claws, do not disappear until she actively dispels them, and also look very cool. The one downside is that generating the armor inevitably shreds her clothes. Each time Sam armors up, it looks a little different, with the suggestion that she's doing this on purpose- which makes sense; Sam's an artist in her day job.

Fan Works

 * In Aeon Natum Engel, The Sword Лu-hvean'tahæn gives the Star Spawn High Priest the ability to manifest it.
 * In Kyon: Big Damn Hero, Kyon's watch has a skin-suit armor function added, which also can be activated automatically to act as an emergency compress.
 * In Jeconais' Harry Potter fic Blue Steel, Harry forges himself several suits of armor which he can summon; they seem to grow out of the ground around his feet, flowing or slamming into place to assemble themselves on his body.

Films -- Live Action

 * In the 1989 Batman a push of a button on the Batmobile covers it in armor.
 * Iron Man: In the second film, Tony Stark has a suitcase that turns into a suit of armor, as a nod to the comics. However, it's more of an Emergency Weapon, as it is significantly less powerful than the regular armour, and apparently only mounts the palm repulsors for weaponry. Still comes in very handy in a pinch.

Live-Action TV

 * The Makai Armour from Garo.
 * A few Power Rangers battleizers have this property.
 * In the finale of Star Trek: Voyager, Admiral Janeway travels back in time to give Voyager this upgrade, allowing a set of nigh-invulnerable ablative armour to be instantly created around the ship. Its frequently referred by fans as "Voyager's Batmobile Armour".

Tabletop Games

 * One of the powers available to Celestial Circle sorcerers in the tabletop RPG Exalted, is to create a huge suit of magical armor, called a Warstrider, and then pilot it from the chest. Seen in action here, in Keychain of Creation, an Exalted webcomic.
 * There are a whole family of more general are more practical abilities, ranging from a humble kata to don your armour more swiftly to summoning and dismissing your suit of magical full-plate armour in an instant from anywhere in creation, or even just packing it away Elsewhere.
 * Dungeons and Dragons
 * One 3.5 supplement has "called armor", allowing you to not only remove the lengthy times for putting it on, but leave it anywhere on the same plane. Psionic's allow you to pull armor (or a weapon) out of somewhere in existence.
 * There's also Mage Armor, Shadow Shield, Ghostly Visage, and so on.
 * The Fourth Edition supplement Adventurer's Vault provides "summoned" armor, which can be of any type, is basically put on the hard way once, and then can be dismissed to and recalled from a "secure extradimensional location" at will, reappearing on the caller's person as though he or she had just put it on. It otherwise functions as plain old magical armor of its given type and bonus (minimum +2).
 * D20 Modern has the gadget "Digital Armor", where your armor is stored as a data pattern on a tiny piece of Techno Babble and can be summoned immediately from anywhere. You don't even need to don it. It's a PL 9 gadget, though, so you are REALLY unlikely of ever seeing it. PL 9 is practically Crystal Spires and Togas.
 * The Pathfinder Advanced Player's Guide contains a spell for Clerics and Paladins called "Instant Armor". The spell does Exactly What It Says on the Tin.

Video Games

 * In the fighting game Evil Zone, special inspector Mikagami Sho used the command phrase 'Zerochaku' to summon his armored suit, becoming the Hot-Blooded hero DANZAIVER!
 * The Sentinel Class' Tech Armor from Mass Effect 2 can be deployed instantly and provides extra sheilding. It also explodes to smack nearby enemies on their asses when it goes down.
 * The highest power of the "Stone Armor" powerset in City of Heroes is "Granite Armor", which surrounds the hero completely with an impenetrable granite suit—making them nearly invulnerable, but also really slow. Its popularity has led to the general wisdom that Stone Tankers shouldn't waste too much time designing their costumes—nobody's gonna see them anyway.
 * The "Junk Titan" and "Pink Titan" Conduits in In Famous are also examples of this (Not sure if there are more "official" names.) The first is a psychokinetic member of the Dustmen, who has pulled together a motley assembly of mainly-metallic trash, into a vaguely humanoid form. The toughest and most annoying unit in the game, hands down. The second, meanwhile, is a telekinetic member of the First Sons, who is basically projecting a gigantic (and very pink) spectral image of himself, stomping around and smashing stuff while his real body floats in the center.
 * In Oblivion the cultists that are responsible for killing the Emperor are able to conjure Daedric weapons and armor from thin air by way of magic. The equipment immediately fades upon their death. Very clever, since it allows for the spawning of Mooks who provides a real challenge, while leaving nothing worth looting behind...
 * In fact, most of the recent The Elder Scrolls games have included Summoning Spells for creating weapons and armor out of the thin air. Powerful, but temporary.
 * In Morrowind, players were still able to enchant rings with permanent daedric armor summoning spells. Depending on the value of the ring and the soul captured, you could have full Instant Armor, without the need for repairs since all you needed to do was remove the ring and put it back on to have a new set.
 * One of the "Suit" power-ups in the Platform Game Vexx works like this. The Rock Suit causes lava-hot stones to surround Vexx, making him invincible and letting him break throuh certain barriers. However, while covered in rock, he runs kind of awkwardly and he jumps like a chump. After a while, the rocks break off and he returns to normal.
 * The main boss of the second dungeon in Beyond Good and Evil is a tiny, easily-damaged mini-Mook that uses some kinda alien telepathy stuff to surround itself with metal machine parts and effectively become a giant, heroine-crushing psychic robot.
 * One of the powers wielded by the shape-shifter Alex Mercer in Prototype is the ability to create a heavy, insectoid-looking armor out of available biomass. Completely covering, and can be sprung out in less than a second... it slightly reduces his speed and agility but makes him much tougher.
 * Or, if you prefer, you can deploy it through a several-seconds long Transformation Sequence.
 * Metroid
 * Samus can put her armor on or off through a mental trigger. Word of God states that instead of willing it on or off, Samus must constantly concentrate just to maintain the armor. To take it off, she simply stops concentrating. Note this only started in Other M. Metroid Prime 3 and Fusion show that the armor stays on her when unconscious.
 * In Super Smash Bros. Brawl, Zero Suit Samus can use a Smash Sphere to instantly assemble her Powered Armor, damaging any nearby brawlers.
 * Metroid: Other M gets into a downright Deconstruction of the "constant concentration" type of armor. Like when and she slowly loses the suit out of physical shock and mental shock that  would do such a thing.
 * In Kingdom Hearts: Birth By Sleep, the main trio wear pieces of armor on their shoulders at all times, and can summon full suits of armor by touching the armor pieces.
 * Producing Instant Armor is the main function of Biometals in the Mega Man ZX series. Mega Man X does something similar from X4 onwards at the start of every stage.
 * In Super Mario 64 and subsequently in Smash Brothers, the metal cap/green block turns Mario/any smasher into a heavy armored version of themselves.
 * In the video game Diablo II, 7 out of the 210 skills in the game are an example of this. Only the Druid, Necromancer, Assassin, and Sorceress can use any of them. All of them, except for the sorceress, who has access to 4 of the skills, can only use 1 of them.
 * Similar to the Granite Form in City of Heroes, Dragon Age II has the spell "Rock Armor" that covers the mage casting it in stone and make it easier to survive in close combat or against archers. There's even a potion that non-mages can use to simulate the spell, and since it has no requirements combined with a low stamina cost it's recommended that every mage take it. And it actually looks pretty cool to boot.

Web Comics

 * The Cyantian Chronicles: Lifts are often stored in a Hyperspace Arsenal and can be summoned at a moments notice. If they're not the size of a small house.
 * Goblins: The Axe of Prissan can create a suit of full plate for its wearer out of thin air.
 * In Flaky Pastry, Gadgeteer Genius Nitrine has a suit of Mega Man-ish powered armor that collapses into the form of a belt-buckle. Usually works as a Super Mode with a 30-second time-limit due to enormous power-consumption, but if she gets her hands on an infinite powersource... watch out.

Web Original

 * During Round 1 of The Book of Stories OCT, one of the entries featured an antagonist doing this with just his walker, tennis balls and all.
 * Alloy from The Descendants does this using whatever metal happens to be available. He actually discovered his powers this way.
 * In the Whateley Universe, Loophole and Jericho can both teleport their armor into place as long as they are pretty close to the armor and teleportation system. They both end up armorless when they're attacked in Boston in "Ayla and the Birthday Brawl". Then there's Iron Star, who can manifest a metal carapace armor around himself whenever he wants. Britomart can do the same with a Guyver-like armor, she just has real trouble getting it off: as a side effect she doesn't have a hair left on her body.

Western Animation

 * Occasionally used by Earthbenders in Avatar: The Last Airbender, making rock-suits for themselves. During the Final Battle, Toph also demonstrates her mastery of Metalbending by making herself a metal-suit on the spot... Being Toph, she also made it a Crowning Moment of Funny in the finale. "Shave and a haircut, two BLAM!!"
 * In the DCAU Justice League, Queen of the Royal Flush Gang could move and shape metal with her thoughts. At one point, she uses it to create a suit of armor and a sword out of casino tokens.
 * More Iron Man, this time as a teenager. 16 years old, and Tony Stark has figured out how to fold up the Iron Man Mk-1 armor into his backpack (equipped with anti-gravity servos so it doesn't weigh him down), with it unfolding and reforming in a matter of seconds.
 * Ben 10: Alien Force: Kevin's powers during seasons 1 and 2 allowed him to create a thin membrane around his body consisting of any matter he was touching. Come season 3, an unfortunate Omnitrix-related accident transformed his entire body into an amalgamation of several materials he'd used in the past two seasons, but this was eventually cured.
 * The eponymous Centurions would have various sets of armor and weaponry beamed onto their person from a satellite as needed.
 * In the Transformers Prime episode "Triangulation", Starscream chances upon a small disc, which - when attached to his chest - spreads around his body, forming the titanic (and unstoppable) Apex Armor.