One-Hit Polykill



"Liara: Is it true you once killed three Blue Suns mercenaries with one bullet?

Garrus: No, the third guy had a heart attack. Not fair to count him."

- Mass Effect 3

Otherwise known as overpenetration in gun-play circles, this happens when a bullet doesn't stop in a body or object once fired.

This can happen when one uses armor piercing rounds on soft targets, but it is more Truth in Television than you might think, even without rifles explicitly using high-powered armor piercing rounds. One of the rules of weapons safety requires a shooter to know what is behind a target and always assume that a bullet will always overpenetrate the first target and still retain lethal velocity.

Also a common weapon or Power Up in Shoot Em Up games, especially when you've got a Charged Attack.

Contrast Bulletproof Human Shield, where the bullets should be able to do this but somehow don't. Also contrast Guns Are Worthless; a game's failure to implement (over)penetration may be a contributing factor to that.

Anime & Manga

 * The Variable Shoot attack Teana used in the third episode of Magical Girl Lyrical Nanoha Striker S, which takes an ordinary magical bullet and coats it with a barrier, letting it penetrate a Mecha Mook's Anti Magic Field to shoot through the Mecha Mook itself, and then continues flying to shoot through another Mecha Mook behind it..
 * Way back in the first season, Chrono's projectile attack, Stinger Snipe, was a tightly-focused guided bolt of blazing blue destruction, cutting through several large mecha in a single pass.
 * This is how  accidentally kills   in Samurai Seven. Though it wasn't just one shot, he was firing a machine gun for at elast five seconds before he stopped.
 * How does Alucard kill a vampire hiding behind a hostage? Shoot through the hostage.

Film

 * Indiana Jones accidentally pulls this on Those Wacky Nazis in The Last Crusade because of the gun used. Indy is visibly surprised when it happens.
 * In Quigley Down Under, the title character does this with an experimental 1800's sniper rifle.
 * "That bastard's been sitting up in the rocks all morning just waiting for two idiots to line up in his sights."
 * Kiss Kiss Bang Bang:.
 * In Bruges: two people end up accidentally killed because of this.
 * Wanted turns this trope Up to Eleven and uses it as near the end: a bullet fired at an angle in a circular room goes through several people's brains before finally lodging itself
 * In one of the Tremors movies Burt fired an armor piercing bullet at one of the Shriekers. The little monster exploded from the impact; the bullet continued through a concrete slab and several empty oil drums, finally using up its energy by destroying the engine of the car Burt was going to escape in. Justified in that the gun and ammo used were designed with the intent of going through tanks.
 * Insinuated in Shaun of the Dead, where after Shaun and Liz manage to evade the zombies in the bar (after accidentally torching the majority of rifle shells), Liz mentions they only have two shells, and Shaun thinks out loud, "Maybe we could take most of them out if they stand in a line."
 * In Schindler's List, during the raid of the ghetto, a group of soldiers force several Jewish civilians to line up chest-to-back-to-chest-to-back...so they can see how many of them a rifle can penetrate. This happens in the BACKGROUND. It's incidental.
 * Invoked for dramatic tension in the Johnny Depp movie Nick of Time: The Dragon and Johnny are in a van, guns drawn. He has his weapon aimed at her head, she has hers aimed at his five-year-old daughter in the seat in front of her. The woman says something to effect of her gun being strong enough to not only blow away the daughter, but the bullets will be able to travel another two miles and kill a few people on the street.
 * In Live Free or Die Hard, John McClane defeats the big bad by shooting a gun through himself into the big bad directly behind him, killing him.
 * The idea is toyed with by the main character in Freejack, who only has one bullet left and knows he will be greeted by a squad of Mooks once his elevator gets to the lobby. Obviously, it is not likely that they would helpfully line up in front of an elevator they're supposed to surround.
 * Gruesomely illustrated by Revolutionary War era cannon (firing a 6 lb solid chunk of pig iron) in Mel Gibson's The Patriot. Wherein a cannonball pulverized its first target, then proceeded to roll on the ground-crushing feet as it went, while coated with the entrails of its first target. It is arguable which soldier had the worse death: the one instantly reduced to chunky salsa, or the one that got to view the rest of the battle while screaming and trying not to bleed out from the stump where his ankle was, just to die from gangrene days later from the infected wound.
 * Done by accident in Killer Elite by the new guy, killing one of his associates.

Literature
Also don't question how he pulled of this trick with a low-caliber hollow-point bullet, or how everyone accepted it was a murder-suicide.
 * Used in the climax of the first Left Behind book, where displays his power by shooting two people with one bullet... and then makes everyone forget that this happened. Don't question how something that nobody remembers counts as a display of power.
 * Jesus using The Word of God to slay the Unity Army soldiers en masse also qualifies as this.
 * In The Ballad of Lucy Whipple, there's a story-within-a-story about an outlaw called Rattlesnake Jake. At one point he shoots a sheriff with a bullet which goes right through the sheriff and ricochets off several other objects before hitting (and killing) a bear.
 * In John Ringo's Posleen War Series, rounds fired from the rail guns used by the ACS, traveling not much slower than the speed of light, will rip through multiple Posleen before running out of kinetic energy.
 * Daffyd manages to pull this off with a longbow in The Dragon On The Border. It's only possible because the Hollow Men are suits of armor with no body in them, and he designed a special arrow intended to pierce armor and keep going, which would be useless against any other opponent.

Live Action TV

 * Xena: Warrior Princess has a bow and arrow example. After returning home from 10 years at sea Odysseus has to fight off an army of mooks with his famous bow capable of cutting through 3 men. Cue a horrific set up where three randoms stand in a straight line behind each other with a precision and timing that would be the envy of any footballing defense, just in time to have a single arrow kill all of them.
 * In the re-imagined Battlestar Galactica, during the liberation of New Caprica, Galactica is heavily outnumbered by FOUR Cylon baseships. Then Lee pulls a Big Damn Heroes by bringing in the Pegasus. Eventually the Pegasus gets torn up so Lee orders an evacuation and points the Pegasus right at a baseship. Not only does the Pegasus destroy the baseship it rams into but its hanger bay, which was blown off during the ramming, flies into another baseship destroying it as well.
 * Both Hernán Cortés' and Ivan the Terrible's guns were able to kill two dummies with one shot in Deadliest Warrior.

Mythology

 * The Odyssey: our intrepid hero demonstrates this tropes with a spear on some unwanted suitors to his wife's hand. It is as awesome as it sounds.

Tabletop Games

 * Some RPGs (including Spirit of the Century and Diana Warrior Princess) have special rules for mooks that allows damage to overflow if you take one out on to the next. This doesn't always represent shooting through someone, but if you're using a gun and you can't think of anything cooler, it often does.
 * Any sufficiently powerful gun, laser, arrow or such can overpenetrate in GURPS but (if you're shooting it at appropriate targets) it's likely to be weakened considerably by doing so.
 * Cannons in Warhammer act somewhat realistically (as noted below). When the shot is fired, a landing point is determined, then the bounce. It's the bounce that usually does all the damage, especially against infantry.
 * Dungeons and Dragons 3.5 has a feat and a magical weapon enhancement, either of which allows an archer to do this as long as they can keep making the attack rolls.
 * The game also has a melee version: Cleave. There's even a unique weapon called The Lance of the Unending Charge that lets you keep on charging until you fail to gib someone.
 * Completely averted in Star Fleet Battles, although this is quite reasonable when one considers that even two starships in the same hex are probably hundreds of kilometers apart--the precise lineup necessary for a polykill would be incredibly unlikely. On the other hand, if a shot does enough damage to completely destroy its target, the resulting explosion could do some hefty damage to nearby ships.

Video Games

 * In Mass Effect 3 it's possible to do this with the Javelin, Widow and Black Widow sniper rifle models by default. Add the Rifle Piercing mod and suddenly every sniper rifle becomes at least capable of doing this, the probability increasing with the higher damaging rifles like the Valiant or the Mantis.
 * Bloodline Champions has a number of abilities that pierce through enemies - most ultimates are capable of this. Always watch out about the formation your team is making.
 * Any game that features a Quake-style railgun will be able to hit multiple people, often through walls.
 * The Metroid games' Plasma Beam.
 * The powered-up shot in Cosmic Gate.
 * Resident Evil 4:
 * The "Punisher" pistol (which can be obtained as a bonus for shooting out several blue targets hidden around the early levels) has the ability to shoot through multiple enemies as its special ability.
 * Although this is already achievable with the more mundane (but still awesome) rifle.
 * Most of the games in the series have at least one gun capable of this. Usually the magnum can plow through multiple zombies, and the shotgun can occasionally manage it.
 * GoldenEye: there are several guns that can shoot through bodies, so if the mooks are lined up right you can easily takes down multiple ones with a single shot, occasionally facilitating accuracy scores above 100%.
 * Same applies in the Online (and local) multiplayer. The Golden Gun has infinite penetration of players (but not walls) and is a One Hit Kill. Even the weakest Sniper Rifle (Silenced Pavlov ASR) can go for multikills, especially if one of them is a Boom Headshot.
 * Makes some game modes, such as the Protection Mission (for the bad guys, MI 6 needs to destroy it) of "Black Box" fairly easy for MI 6 on the wider maps. Mainly because the default gameplay is to have one person with said box (who then moves slowly and can only use a pistol), and everybody else clusters around bristling with automatic weapons to ward off surge attacks, cue 3 or 4 deaths with a single silenced round.
 * This can happen in Halo with the sniper rifle, and you can download several people's replays of it
 * You can definitely do this in the first two games in the series as well, if you can line up a pair of Grunts / Jackals.
 * Even more impressivly, a single spartan laser shot in Halo 3 can demolmish 10 jeeps at once.
 * War Craft 3 units with the Missile (Line) attribute can do this.
 * The same attribute is present in Star Craft 2. There is even an achievement for killing 50 mooks with a single penetrating shot in campaign.
 * The hunting rifle in Left 4 Dead.
 * All of the stronger weapons in Left 4 Dead can overpenetrate, with varying amounts of effectiveness (from the "goes through anything, including walls" hunting rifle to the "as many zombies are within 50 meters" shotgun. Makes fighting those 30+ hordes of zombies easier than you'd think.
 * Team Fortress 2:
 * While this feature has since been patched out of the game proper, in the "Meet the Sniper" video, the Sniper fires a bullet through a Heavy's head and into the Demoman's bottle, shattering it and causing him to panic (and then strike a wall while holding the bottle close to his face, getting the neck stuck in his eye, draw his grenade launcher and fire randomly, then fall off a ledge into a bunch of Exploding Barrels under it as his grenades fall there as well, and explode.)
 * The Sydney Sleeper used to be able to do this with a full charge, but the ability was removed shortly after its release (and a while later it was given a shorter charging time to compensate).
 * One of the Soldier's secondary weapons, the Righteous Bison, fires energy bolts that never stop until they hit a wall, making it great for bottlenecks. Interestingly, the weapon deals damage to each target multiple times (one hit every 45 milliseconds), which allows it to deal more damage to targets running away.
 * An unlockable weapon for the Engineer, the Pomson 6000, uses the same projectiles with an added Mana Burn attribute.
 * The Sniper's new weapon, The Machina, penetrates all targets--except buildings--with fully-charged shots, and unlike the old Sleeper it can still get headshots. It even has separate kills icons for bodyshots and headshots that went through someone else first, and a special sound that plays to everyone in the server when you actually manage to get either (whether or not the target it went through died).
 * In Diablo II, the Amazon has a Bow skill called Pierce, which causes arrows to pass through multiple enemies. When combined with Strafe, which splits an arrow to hit multiple targets... carnage ensues.
 * In older versions, this produced amusing results when used with the "guided arrow" skill - the arrow would hit the target, fly out the other side, and immediately turn around to have another go (and possibly repeat up to 5 times).
 * Some projectile weapons also have the Piercing Attack trait, rated 1 to 100% chance to pierce a target. The Buriza-Do Kyanon unique crossbow was the preferred weapon of many Amazons, called "Burizons", who specialized in Strafe and (when it worked) Guided Arrow.
 * As well as this works with bows, it works much better when the Amazon uses a Javelin. Her Lightning Fury skill makes a number of lightning bolts fly out towards the enemies and at high levels you get a very high number of bolts. Combine it with piercing and the javelin will go on to hit another target... and release the entire volley of lightning bolts again. And again. And again. The more enemies you have together the faster all of them will drop dead, making this perhaps the ultimate example.
 * Bullets do this sometimes in Jagged Alliance 2. In keeping with the game's complex, pseudo-realistic mechanics, this mostly happens with heavier bullets, armor-piercing rounds, and hits to unarmored enemies.
 * In Command and Conquer: Tiberian Sun, GDI railguns would penetrate through anything standing between the shooter and the target (read: Friendly Fireproof isn't in effect here), dealing equal damage along anything in that line. Because of the extremely high damage output invested in every shot, a railgun is quite lethal to fragile targets. Canny gamers would then set these weapons to force-fire behind the unit or structure they wanted to kill.
 * Another weapon that polykills is the GDI sonic emitter, first used by GDI Disruptor tanks from the same game. It's essentially a railgun with more sophisticated rules: the emitted sonic beam takes time to reach its target, hurts less to anything in between that's not an intended target, and hurts friends and foes alike, unless it's another Disruptor. In short, it's safe to cluster Disruptors among themselves, but not with other kinds of things. This reappears as the Shatterer (and upgraded ZOCOM-only version, the Zone Shatterer) in Kane's Wrath.
 * In Command and Conquer Red Alert 3, Natasha's sniper shots kill any and all infantry units in their path. Force-Wave Artillery is capable of it as well, albiet every target past the first unit hit will suffer less damage.
 * In the original Unreal Tournament, it was not possible to do this with the InstaGib weapon (the modified Shock Rifle). However, UT2004 changed this weapon by allowing the beam to pass through multiple characters. This took away the satisfying effect of the beam stopping at the location of the hit.
 * The Ballistic Weapons mod takes this one step further: the Tactical Infantry Cannon (big-ass scoped railgun) which, at full charge and using the scope, can shoot through the entire map and still overpenetrate a tank, insta-killing both the tank and whoever was standing behind it. And that's a man-portable weapon we're talking about here. Now imagine what it does against man-sized targets or lighter vehicles...
 * Call of Duty series:
 * Call of Duty 4: Modern Warfare has this in spades, and players die from the effects of this trope all the time. The body of a fellow player will weaken bullets, but it won't stop them unless they have already lost a lot of momentum. For the more powerful firearms, such as the sniper rifles and the light machine guns, overpenetration is the norm.
 * In Modern Warfare 2, there are multiplayer challenges requiring the player to get two headshots with one bullet or two kills with one sniper shot.
 * Not to mention an achievement for doing so.
 * Call of Duty Black Ops ups the ante with an achievement for getting three kills with one bullet.
 * Many players of Call of Duty know of terrible impending deaths in multiplayer in which they saw an enemy player be in a position to shoot at them, but an ally (or allies) of the player was in the way. Due to Friendly Fireproof, you cannot harm your allies or anything behind them with bullets. The enemy can harm your allies and everything behind them (like you), though.
 * Though not actually a single shot in most cases, the turn-based nature of Fallout means that it's very rewarding to run right up close to a cluster or row of enemies with your minigun and tear their torsos to shreds in one attack (or, even more hilariously, go hand-to-hand in heavy armor amongst enemies so armed and watch as they obliterate each other.) Sadly, this also means that your "buddies" are often prone to hosing you down from behind if you give them automatics.
 * One NPC in Fallout New Vegas claims to have done this if you ask how he killed 4 men with only 3 shots. It turns out that the men are just playing dead and are in on the scam.
 * Somewhat similarly, since dying enemies in early games became nonentities physics-wise (that is, immediately upon dropping below 1HP, all shots go right through them,) multi-pellet shotguns in FPSs like Doom and Marathon 2: Durandal punched through whole columns of weak or damaged enemies in a single shot.
 * The rocket launcher in Wolfenstein 3D's Mac and IIgs ports.
 * The fusion cannon in Descent. Not only does it go through an enemy robot, the shot actually becomes stronger after doing so.
 * Fully charged arrows from the Bow of Light in any The Legend of Zelda game where they're featured.
 * Silent Storm. Oh boy. The realistic damage modelling means it is entirely possible to kill someone standing behind a wall with a high-caliber bullet. And if there's no wall, the bullet can still penetrate multiple Mooks and knock them back a few metres (bear in mind these are WW 2 weapons we are talking about). Aaaand there's where the sniper's Shoot Through Cover (completely removes the advantage of cover for the target) and Always Inflict Ranged Critical perks come in handy...
 * The fully Charged Attack of Mega Man's Buster weapon is capable of doing this, provided it doesn't hit a durable target.
 * 1's Thunder Beam is another notable example.
 * Same with 2's Metal Blade.
 * ROM Hack Rock Man 4 Minus Infinity has Water Cutter and Drill Torpedo.
 * In the Munitions powerset of Champions Online, the Sniper Rifle power can take an advantage called "Tungsten Rounds", which enables it to hit up to three targets in a line up to the maximum range of the attack - against Mooks, this is often one hit polykills.
 * One level in Hitman 2 allows you to kill two targets with one shot if you line it up just right.
 * The original(pre-source) versions of Counter-Strike and Day of Defeat (and probably other half-life engine games) both exhibited this with some weapons, mostly Rifles. These weapons could penetrate doors, crates, ventilation ducts, and other 'thin' or 'soft' materials... including Players. With Day of Defeat's one-hit-kill (even in the TOES) bolt-action rifles, this occasionally resulted in two Players literally being killed by one shot. THREE with one shot was perfectly possible, but very rare and requiring more luck than skill.
 * The Demonspine spell in Hellgate London penetrates with perfect accuracy up to 30 meters, potentially killing anything in it's path.
 * Unlocking the Terror Scoped Rifle in The Saboteur requires the player to make ten such shots.
 * The Sniper Rifle-type weapons in the Ratchet and Clank series are generally capable of this when upgraded.
 * The Special Weapons class in Alien Swarm gets the Piercing Bullets ability, which gives each shot fired a chance to do this.
 * The laser in Duke Nukem II.
 * In Tyrian, the Mega Cannon did this. It could even damage larger enemies more than once as it passed through them.
 * Same goes for the Plasma Storm, a giant cloud of fire that did continuous damage to whatever passed through it.
 * Essential in Survivor the Living Dead, as your have to carefully ration your ammo. It's also one of the determining factors in your score at the end of the game, and since getting a high score, or high number of kills is how you unlock some of the weapons and bonuses you'll need for the harder difficulty settings this makes mastering the One Hit Polykill the most important skill the player can master.
 * The massively powerful maximum-level ability for archers in ADOM is just this, enabling their arrows (or even just rocks) to go on as long as they please without being stopped by creatures in their path.
 * Kiai Scrolls in Teenage Mutant Ninja Turtles penetrate everything and can 1-shot all but strongest foes. Boomerangs can also do this on weak enemies.
 * The Sawblade Cannon in Gun Girl 2 exists purely to do this. One of the upgrades also increases the number of enemies the sawblade can chew through before being destroyed. Useful, since a major source of danger is gigantic hordes of zombies spawned from Clown Car Graves.
 * It's possible to hit two or even three targets at once in Silent Scope if the Mooks are standing in front of each other.
 * Some weapons in Cave Story can do this, most notably the Spur, which functions as a Frickin Laser Beam or a Wave Motion Gun depending on how long you charge it.
 * In Dragon Age 2, Varric describes himself doing this in one of his Unreliable Narrator moments. Any rogue (besides Isabela, who cannot equip bows) can also do this in-game with the upgraded Archer's Lance talent, which travels through enemies and one-shots all "weaker opponents" it comes in contact with.
 * The Scattershot archer talent in the first game also allows this, provided the enemies are weak enough. An archer can clear a whole group of Grunt type enemies with one shot--though a quirk of the mechanics means that that first shot has to targeted at something that will survive it, otherwise the spread effect doesn't happen.
 * One fully charged cannonball from Serious Sam's cannon can penetrate dozens of enemies of size up to 5 meters.
 * Mortal Kombat Shaolin Monks has a version of this. When the time comes to Finish Him, you have a couple of Multalities you can perform, which will kill all enemies within range.
 * Rockman Minus Infinity has the Drill Torpedo and the Water Cutter. Drill Torpedo is justified because Mega Man fires drills. Water Cutter is an ultra-focused and ultra-quick water blast.
 * In Jamestown Legend of the Lost Colony, the Beam (continuous fire) and Charge weapons (single shot) can do this.
 * Bulletstorm has multiple weapons that can do this. Pulling off these One Hit Polykills results in an exponential increase in points for each extra mook beyond the first two.
 * In Super Smash Bros. Brawl, Zelda's and Sheik's Final Smash, the "Light Arrow," will hit any characters in their line of sight, passing through everybody until it hits a wall or the boundaries of the stage.
 * Similarly, ROB's laser attack hits through anyone in the line of fire, making for a useful kill move, or at least knocking back several foes at the same time.
 * Armor Games' The Last Stand Web Game series. Bullets from several weapons can go through (and kill) more than one zombie at a time.
 * The Last Stand: the sniper rifle and the Barrett rifle.
 * The Last Stand 2: the sniper rifle.
 * Crazy Monkey Games' Web Game Zombie Horde 2. The Decapitator can fire through (and kill) more than one zombie at a time.
 * The Bridge level in Syphon Filter 2 requires you to get a double kill with the sniper rifle to save a pair of hostages.
 * The Line Gun in Dead Space fires off a meter wide cutting laser. Unlike it's kid brother the Plasma Cutter, this cutting laser is not stopped when it hits a target. A well aimed shot can take off both legs of several necromorphs.

Web Original

 * Halo x Metroid Fan Vid Haloid takes this to the max with a combination of two thrown energy shields (the kind that reflect bullets) and one sniper round result in a massacre of several dozen mooks. Probably all head-shots, too.

Western Animation

 * Parodied in Rango, where the titular character claims to have killed the Jenkins brothers with one bullet only to find out there were seven of them. He then has to make up an incredibly contrived tale of how such a thing could possibly happened.

Real Life

 * Some musket-balls do this. Historically, given that they were shot at two and three rank lines (or even eight-deep columns) it doesn't seem all that hard to believe.
 * One rule of Roger's Rangers was to march far enough apart such to prevent a musket ball taking out two soldiers at once, so it's very probable.
 * It is pretty hard to achieve through-and-through hit with relatively low-powered lead spherical projectiles. Glancing multi-hits on the other hand were pretty probable.
 * Round-shot ("cannonballs") very often did that, often getting an average of more kills then rounds fired. As they had more heft then musket-balls, it isn't hard to imagine. Perhaps you do not wish to imagine what it looked like.
 * By "more heft", it means "a 20 lb sphere of pig iron". One-shot polykills were common. Even 6-lb field artillery projectiles were known to drill a straight line through the enemy, not difficult when the enemy is standing in massed ranks before you.
 * This is actually the whole point of the field artillery. To remove multiple targets from battle with a single hit.
 * The "single bullet theory" of John F. Kennedy's assassination, which argues that a single bullet passed through the president's body and then struck John Conally, who was seated below and forwards of Kennedy. Recently demonstrated on the History Channel via computer simulation to be relatively plausible.
 * Also almost entirely replicated by an expert sharpshooter for a Discovery Channel special. The only difference between his shot and the real one was that the bullet didn't have quite enough energy to get into the Conally model's "leg" at the end of the trajectory. Examination of the models showed why: Conally had a single rib broken by the bullet as it went through him, while the replicated shot had hit two ribs as it tumbled, losing just enough energy to prevent the additional penetration.
 * There is a game based entirely around recreating the shot. It's not an easy task..
 * An M1 Abrams tank fired a shell through an enemy tank... and hit another enemy tank.
 * And it went the other way in WWII in Europe: The long-barreled 88 millimeter gun on the German Tiger tank could punch right through an American-made M4 Sherman with enough power left over to kill another one on the other side.
 * Rather chillingly invoked by the Nazis for mass executions, in order to save bullets. Turned out it was still too traumatic for the soldiers tasked to do it, hence the development of the Final Solution.
 * Simo Häyhä once shot eight Russian soldiers with one bullet. They thought they were being attacked by multiple snipers, and ran away.
 * One of the reasons why police (unlike soldiers) use hollowpoint and other such controlled expansion/frangible rounds. In war it's assumed that the man behind an enemy will be another enemy. The police shoot people in an environment where the person behind their target is likely to be an innocent bystander.
 * Not exactly - hollowpoints aren't normally used in war because of the Hague Convention banning them as 'inhumane.' Many armed forces still use them in specific situations, however, Hague Convention be damned.
 * A hunter in Sweden got into trouble with the law, because he killed two moose with one shot. He was only allowed to kill one.