Polarity

Polarity is a Spiderman fanfic featuring small-time villain and engineering genius Herman Schultz, aka the Shocker, who takes up the role of Accidental Hero as he saves a French woman from a zombie. The story follows the Shocker and his partner Aleksei (also known as the Rhino) as they seek to protect themselves and the disparate grouping of folks they pick up from both the undead horde and the seemingly incompetent government, gradually becoming more and more heroic as they go along.

There is a sequel called Transistor.

Tropes used in Polarity include:

Adaptational Badass: Several villainous characters, including admittedly the Shocker and Rhino.
Amplifier Artifact: When fighting against a zombified Rhino in a museum, the Shocker gets his hands on a NASA air compresser, allowing him to vastly increase the power of his vibro-blasts.
Anyone Can Die: Rhino, Electro, Vulture, the Hulk and Baron Mordo are among the more major characters who die within the story, the first's death being particularly shocking. Hercules, Falcon, Echo, Luke Cage and Black Widow are all mentioned in Transistor to have died during the events of Polarity, though their deaths aren't referred to in the first story.
Badass: Shocker, Rhino, the Punisher, Thor, Ms Marvel. Basically every character in this story with a pulse and a costume.
Badass Normal: The Shocker takes on zombie hordes, superheroes and supervillains, all without superpowers.
- The Punisher is another example. He survives attacks from zombie hordes with limited firepower, and is later extensively tortured by Grim Reaper till he nearly dies, and still manages to kick ass and scare the Shocker in this weakened state. The Shocker may do more, but he's got the advantage of highly advanced gadgets; the Punisher just has guns.
Bad Guy Bar: The canonical Bar With No Name. By Transistor Boomerang is co-owner, and it's instead a reformed villain bar.
Big Applesauce: The whole story could be considered a love letter to New York City. Herman himself is a born-and-bred New Yorker, along with being a diehard Jets fan. Plus, the author not only gets the layout and geography of the city right, but uses fictional places like Yancy Street to great effect.
Big Bad: Eric Williams aka Grim Reaper may lead and have created the zombie horde, but his boss is Dormammu.
Bilingual Bonus: After rescuing a little girl from a horde of zombies, Batroc the Leaper tells her, "Venez, enfant. Je vous prendrai a la maison," which translates to "Come on, child. I will take you home." He then turns to the man hiding behind a closed window who had been filming the whole thing on his cell phone and tells him, "Dissimulation derriere l'acier tandis qu'un enfant est mis en danger. Vous n'etes aucnu fils de la France." Translation - Hiding behind a closed door while a child is in danger. You are no son of France."
Boom! Headshot!: It's a given in a zombie story. Luckily blasts of vibrated air do as good a job as bullets on zombies' brains.
Breaking the Fourth Wall: The story is written as if it is being told to the reader by the Shocker himself.
Cruel and Unusual Death: Norman Osborn is ripped apart by zombies from the original Marvel Zombies universe, including the zombie of his own arch-enemy.
Did You Just Punch Out Cthulhu?: At one point the Shocker faces off against a undead Hulk, using his vibro-smashers at maximum to dissolve the floor beneath him and drop the creature straight onto an exposed piece of broken pipe.
- The final epic battle in New York between Dormammu and every hero and villain in the city. They manage to knock him down and banish him to Limbo in his weakened state.
The Dragon: Dormammu's lieutenant was at first Eric Williams aka Grim Reaper, but once he is defeated in battle with the Avengers, Dormammu replaces him with Electro, after giving him a power boost.
Enemy Mine: Shocker ends up fighting alongside the Avengers against the most dangerous threats. He even has a cordial chat with Spidey. The supervillain and superhuman communities collectively have this reaction to the zombie threat, although with some exceptions.
- This is a major point of the story- heroes and villains fighting together to survive and defend humanity.
Even Evil Has Standards: The reason why Shocker and Rhino head out to save a group stuck inside a store assaulted by the undead. They may be criminals, but they can't sit by and watch on TV others suffer a horrific death when they can help. The Shocker also considers rape as a particularly disgusting act.
- As in the normal 616 universe, The Hood considered a zombie virus too dangerous to use.
Flying Brick: Ms Marvel, Thor and Wonder Man are some of the more important Marvel heroes
Good Feels Good: One of the factors that influence Shocker going on the straight and narrow
Hard Light: The Living Laser is one of the very few super humans who cannot be harmed by the zombies in any way. Their bites and scratches have no effect on him, as he is no longer organic- this is one of the reasons that he volunteers later to help the heroes. In Transistor it's theorised that X-Ray of the U-Foes has similar invulnerability, as he is instead solid radiation.
Heel Face Turn: Many supervillains either retire or join the side of good during and after the invasion, seeing this society as a chance for a new start, and realising that supervillainy is now pointless in a now largely lawless world where superheroes will react more harshly. By the time of Transistor some have even joined hero teams, including Shocker in the Avengers, Speed Demon in the Thunderbolts and Hydro-Man in SHIELD.
Hero Ball: Averted largely. The heroes are always shown acting intelligently, and it is clear that without their aid New York would be overwhelmed easily. But they do allow Norman Osborn to take emergency leadership of the US, as he does so legally and the public need to see their leaders as united. However the heroes aren't happy about it, keep a close eye on him and would happily remove Osborn, so this is understandable.
Hybrid Monster: Several superhumans come back to life as zombies during the story. The more important ones include the Hulk, Electro, Dormammu's servants and Rhino.
Improvised Weapon: In order to breach a magical force-field of the highest order in a museum, the Shocker needs to use an ancient weapon of great power. So he stabs it with a bone from a nearby T-Rex skeleton.
Informed Ability: Subverted. In the comics, Shocker is said to be a master safecracker and expert on security system, but normally, he's just shown blasting his way through walls. In the story, Shocker uses his security skills to crack open a Tony Stark designed vault in the middle of a blackout, using Electro as the power source.
Jerk with a Heart of Gold: Shocker and Rhino may be criminals, and the Shocker may have considered killing someone for money during his his villainous career, but they can't sit by when they know innocents are in trouble. Indeed both state later that they wish to heroes.
Let's Get Dangerous: Electro and the Vulture demonstrate in this story exactly how dangerous they can be.
Loads and Loads of Characters: The amount of Marvel villains in this story is impressive. Once you start to count the heroes too, you realise the scope and detail of this story, with characters as diverse as Black Talon to Nick Fury, with really obscure villains like Blizzard.
Nice Job Fixing It, Villain: After the Shocker is poisoned by Norman Osborn and left to die in the streets, he is rescued by undead Electro to recruit him to Grim Reaper's alliance, allowing him to be rescued later by Spider-Man and Boomerang.
Nigh Invulnerability: Zombie Hulk simply shakes off any damage Thor and Ms Marvel land on him, barely being stunned by their most powerful hits. This is because once he was bitten by a zombie, he just kept on getting more and more angry when the wound didn't heal, getting stronger all the time.
- The red-eyed sentient zombies, such as Black Talon, are also really difficult to kill. He simply pulls himself back together after being partly exploded into little chunks of meat.
Won't Work On Me: As the zombies are of a magical origin, their bites and scratches can bypass the invulnerability or heightened durability of most super humans. Zombies manage to cut and draw blood even from Thor and Rhino. However armour is not affected by the quality of the zombies, so heroes and villains who rely on power suits etc. for protection are harder to bite.
Not So Harmless: B-List and C-List villains such as Electo, Vulture, Grim Reaper and the Shocker himself are shown to be powerful and quite savvy fighters. Electro in particular shows the logical danger he poses with his substantial powers.
Our Zombies Are Different: These zombies are similar to Romero's classic zombies, in that they are slow, dead, rotting and unintelligent. As well anyone who dies without the brain being destroyed becomes a zombie, and their bites infect, kill and reanimate the victim. However these zombies are caused by a virus used and introduced by Dormammu by sacrificing the Hood using the Grim Reaper as his servant. Additionally some zombies can be possessed by Grim Reaper, as shown by their red eyes to make them more effective. A second type of zombie is later introduced which are magically preserved, red-eyed zombies who can't heal from their cause of death, and retain their intelligence and memory to better serve Dormammu and Grim Reaper.
The Paragon: Shocker becomes a more grounded version of this, inspiring many supervillains to band together with the rest of humanity against a common enemy, rather than selfishly acting for themselves
President Evil: Norman Osborn has been effectively placed in charge of the USA in order to deal with the zombie threat. Sure nothing bad can happen...
Punch Clock Villain: Throughout the story, Herman talks about what he does when he's not saving the world from zombies. Such activities include drinking, tinkering with his gear, and even going to a planeterium laser-show with fellow villains Speed Demon and Blizzard.
Red Eyes, Take Warning: This is a sign that a zombie has been magically preserved with its original mind and will heal from damage, or that it's been possessed by Grim Reaper.
Removing the Head or Destroying the Brain: The only way to take down regular zombies is to destroy the brain, which Shocker's vibro-blasts do nicely. Superhuman zombies are naturally harder to put down, requiring more inventive attacks on the brain, such as Hydro-Man flowing into Zombie Hulk's head through his orifices, and then crushing his brain with water pressure.
- It doesn't work as well on the sentient red-eyed zombies though, as they can use magic to pull themselves back together if just shot in the head.
Science Hero: In order to put down all the zombies in the world for good, Herman applies his knowledge of science to laws of magic to have them all Rest in Peace.
Shout-Out
- The Shocker states that the idea of him going legit is about "two-thirds plausible"
Sliding Scale of Anti-Heroes: Rhino and Shocker are somewhere between type I and type II, with Shocker further down the scale. However both essentially graduate to clear hero status later in the story. The Punisher remains solidly at type IV though.
Technical Pacifist: Herman is stated as being this prior to the Zombie Apocalypse, because he plans all his criminal jobs in order to minimise civilian casualties. It doesn't stop him from putting zombies back in the ground though.
Took a Level in Badass: Shocker takes several within the story, as does Electro.
Zombie Apocalypse: Do I really need to explain this? However as the zombie attack does not last very long, when it ends a couple of billion of people survive.

Its sequel Transistor provides examples of:

Apocalypse How: Earth ends up somewhere between Class 0 and 1 after the events of Polarity. A few billion people were killed, with entire cities such as Boston wiped out. Furthermore some super villains have taken over territories (such as the U-Foes in Los Angeles), Latveria has closed off all contact with the outside world and a new breed of zombie has returned, so things may get much worse . Money now has no value, and superheroes have to work around the clock to put down signs of trouble. However humanity still has nearly all of its technology, organisations such as S.H.I.E.L.D. and super humans to repair the damage, so the future doesn't look too bad.
Badass Boast: "He’s Ares. He’s the damn God of War.” “He is ONLY the God of War. I am Baron Helmut Zemo. And I say, let the dead come to claim me if they dare.”
Big Bad: Say hello to MODOK and his lackeys from Advanced Idea Mechanics, aka A.I.M. Subverted however in that MODOK is being held prisoner in an old A.I.M. facility, so now we don't know who's behind the new zombies.
Dangerously Genre Savvy: The mysterious villain behind this new outbreak. He recruits old supervillains to perform his plans, but reveal minimum details to them to make sure the Avengers can't trace them back to him. He mindcontrols his zombies directly to ensure maximium efficiency, uses complex military tactics, and uses standard Marvel universe technology such as teleportation to great effect. He also releases information on the zombie outbreak before the heroes can to CNN and manipulates the footage to show the heroes and Shocker particularly in the worst possible light. This guy's good.
Dropped a Bridge on Him: Hercules, Falcon, Echo, Luke Cage and Black Widow are mentioned to have died during the zombie apocalypse, but their deaths aren't shown. Justified though in that the whole world has gone to hell, and many superhumans were probably killed, and that zombie bites still affect superhuman flesh.
Fire-Forged Friends: Shocker gets on well with Ares, and was even sponsored for membership in the Avengers by Thor, after fighting along side both. However it's Ms Marvel who is now Shocker's closest friend in the hero community.
Genre Savvy: The heroes are now more prepared than ever after undergoing a near apocalypse. The Avengers are sent in squads of about 3-4 to minimise losses and 'Code Black' is prepared for if zombies re-appear, which includes monitoring hospitals to see if any recently deceased rise.
Hannibal Lecture: Electro gives one of these to Herman when he visits him in a SHIELD prison cell, telling him that all it takes it one bad day for all the trust and goodwill he's earned to go away.
High Altitude Interrogation: Moonstone flies into the air with a mook and drops him at a height she tells him in great detail would cripple him. Luckily Spider-Man webs him a safety net, yet he still manage to convince the mook that next time he might not.
Hollywood Tactics: Completely averted by the heroes. They set up barriers to force zombies through choke-points they can concentrate their fire into, use ranged and melee fighters to defend each other and cover each others weaknesses, use effective search and destroy tactics against hiding guerilla zombies, consider military airstrikes against zombie hordes, snipe zombies from stationary and safe positions etc.
- Also interestingly averted by whatever supervillain is mind-controlling the zombies. Instead of having them just attack as a mindless horde, they split up large hordes to divide the heroes' attention, specifically attack civilians for greater distractions, and have the zombies practise effective urban guerilla warfare.
It Got Worse: Zombies are back, but now they can sprint as fast as Usain Bolt without tiring. Plus there seems to be some sort of conspiracy recruiting super villains as henchmen behind this new outbreak.
Just Friends: Shocker spends a lot of time insisting to others and the reader that this is the case with Ms Marvel.
Loads and Loads of Characters: In addition to much of the characters from the previous story, Baron Zemo, Songbird, the Spymaster, the U-Foes, Titanium Man, and the Griffin have all shown up in one capacity or another.
Mythology Gag: "I'm sure Reed Richards would take the proper precautions," Moonstone countered, hands on her hips. "A man like him would never let a zombie infection spread."
Our Zombies Are Different: A third type of zombie is introduced in the sequel, vastly different from the other two. Their circulation system and certain organs still function and work better than athletes', although the good guys have no idea how, as the heart and lungs no longer work. The result is that these zombies act as if they're on a constant adrenalin high and produce no lactic acid, allowing them to outperform normal humans, being faster and stronger.
Power Armor: The Shocker's "quilt" suit is upgraded even further, with more sensors and more powerful gauntlets. In addition Mach-V is now Shocker's main partner.
Put on a Bus: Iron Fist, Moon Knight and the Punisher have disappeared, and no one's quite sure where. The Sentry also departed into space after a chat with Dr. Strange.
Retired Badass: Just because Boomerang is now a bartender doesn't mean that he can't throw a mean razorang.