Speed Blitz

Some people are fast. Some people are very very fast. Some of them travel so fast you can't even see them move.

And sometimes these people will fight so fast you hardly even get to react. That's a speed blitz.

Fights like this can end before bystanders even know it has started. As the name suggests it's more being hit by lightning than getting in a brawl. A common version of this in Anime is to Flash Step past a person and strike them in a process, never slowing down enough to be seen.

Can be a serious source of Fridge Logic for speedsters. After all if they can fight like this why don't they do it all time? The Doylist answer is Rule of Drama, it's hard for a non-speedster to resist a Speed Blitz so if it happened all the time there would be no tension. Watsonian answers usually call on some Necessary Drawback; maybe this use of speed is damaging to the body or creates sonic booms that will harm bystanders.

Named after a common term in internet fight threads, itself probably a reference to the Nazi tactic of blitzkrieg.

If the blitz takes the form of a hail of punches, it's Rapid-Fire Fisticuffs.

Compare Single-Stroke Battle.

Anime and Manga

 * Rock Lee from Naruto tries this on Gaara during the Chunin exams. It only fails due to Gaara being Nigh Invulnerable compared to the other entrants.
 * In Dragonball Z, Trunks encounters a group of Frieza's henchmen. In a single Flash Step, Trunks manages to Clean Cut all of them.
 * It was actually parodied in the original, early battles of Dragon Ball, before it could even become a trope. In the Tenkai Ichi Budokai tournament, Kame Sennin (in disguise as "Jackie Chun") fights Krillin. The fight is over before the audience can even blink. Annoyed, they demand a better show, so Jackie Chun and Krillin go back and sloooooowly reenact the dozens of attacks, feints, blocks, defenses, and even taunts that they used in that split-second, complete with helpful commentary.
 * This is how the Flash Step is introduced in Bleach, with Byakuya using it to beat up Ichigo so fast that Ichigo can't even see what's happening.
 * And then Ichigo's Bankai makes him so fast that it looks like there's a swarm of Ichigos flying around.
 * But of course Yoruichi The Goddess of Flash once took out dozens of Mooks in the blink of an eye. With her bare hands. Despite having been out of practice for roughly a century.
 * In Claymore the Flash Sword and Wind Cutter techniques unleash a storm of iaido-style slashes so fast that weaker characters cannot tell the user has moved, and powerful enough to disintegrate a tree in seconds.
 * Racer from Fairy Tail does this to Gray and Lyon.
 * Near the end of Magical Girl Lyrical Nanoha StrikerS, Fate activates Sonic Drive and demonstrates how much faster she is now by dashing past Sette, slicing up her Boomerang Blades into itty-bitty pieces, and taking her out of commission all before she could even move out of her ready stance.
 * Famous example from Yu Yu Hakusho: Hiei vs. Seiryu. Seiryu is fast enough to throw a hundred punches in a split second. Their fight ends in seconds, Hiei having slashed Seiryu sixteen times with his sword, before Seiryu even knew he was cut.
 * Hiei seems to love this trope, as he repeated something just like this in the Dark Tournament in his "fight" against Makintaro. Hiei takes out his sword. Next thing Makintaro knows, his arm's been cut off. Hiei then proceeds to hold said arm in the air, and only then does Makintaro realize what's happened, and cry out in pain.
 * Luffy from One Piece upon entering Gear Second. In more recent arcs, he can enter this form quickly and exit out of it easily, so most of his attacks are in this form.
 * CP9 agents are fond of this with their Soru technique. The most basic way to assassinate someone is to Soru over to them, then use Shigan to quickly hit them with the force of a gun. Luffy actually invented Gear Second specifically to duplicate Soru's speed.
 * Yaiba is very fast and sometimes he/or his enemy can reach such a level of speed.
 * In Mahou Sensei Negima, this trope is used in several ways:
 * First, there is "instant movement". By using it multiple times, high-level fighters can traverse large distances extremely fast to overwhelm opponents.
 * Next, learns Magia Erebea, which not only drastically speeds him up on its own, but also allows absorbing spells, including absorbing lightning spells to give him lightning speed.

Comics

 * The Flash is fond of this method against mere mortals.
 * So is Superman.
 * And Thor. He once shut down Quicksilver in a heartbeat when the speedster got a little too cocky.
 * Quicksilver in The Ultimates was infamous for claiming he saves all his teammates' lives multiple times without them seeing it. They assume he's lying. However we see it first hand when he takes down Hurricane. The fight starts as Hawkeye is knocked over and ends before he hits the ground. Naturally he complains that Quicksilver should have done something to help.

Fan Works

 * Doug Sangnoir of Drunkard's Walk can "combat hype", during which he is several times faster than a normal human. Even without hyping he is occasionally described as moving so fast he seems to blur. If events in Drunkard's Walk II are any indication, this is a trope shared by almost all of the Warriors (the super-team of which he is a member), among whom Doug is merely mid-level in speed. (This is a result of expressing the Villains and Vigilantes combat and initiative system in "real world" terms.)

Literature

 * Possibly the most extreme example is The Shrike from Hyperion. Late in the series, it repeatedly blitzes people who are themselves so fast that they can watch lasers crawl through the air in front of them. It's probably best not to think about the physics of that.
 * In detail: it destroys every light in a tunnel system nearly simultaneously, then retreats several miles in a fraction of a second so that a radar scan doesn't detect it, then runs back down, waits for its enemy to turn on her own superspeed powers, and finally pulls out her intestines before she can react. Turns out that when you blast the Shrike with a Kill Sat it kind of holds a grudge.
 * The Garatron in one of the Animorphs books.
 * The Andalites have shades of this as well. They can move their tails fast enough so that most species can't even see anything before their throat is slit.
 * The Fighter-type specialists in Sergey Lukyanenko's Genome move and fight so fast, others (like the protagonist, a Navigator-type) barely notice that a fight broke out before one of the Fighters drops dead or incapacitated a second or two later. Needless to say, nobody but another Fighter-type can fight them at all.

Web Comics

 * In this Ask Axe Cop comic, Axe Cop explains how he became the world's fastest chopper by downing a can of Red Bull and decapitating 1,000 bad guys at once.
 * Bro Strider in Homestuck can move so fast that he can and does fight by using Lil' Cal, essentially fighting using real time stop motion.
 * Dave on the other hand is a Time Master and uses it to make his Flash Step seem faster, though he's genuinely pretty quick himself.