Apocalypse How / Class 4

Apocalypse How
0 | 1 | 2 | 3a, 3b | 4 | 5 | 6
X | X-2 | X-3 | X-4 | X-5 | Z

Earl Sinclair: Maybe we went a little overboard with the poison.
Charlene Sinclair: A little? Your stupid spray killed all plant life!
Earl: Hey, what are you complaining about? You never liked salads anyway.
Robbie Sinclair: You've destroyed the global food chain! No plants means no food at all!

— The Sinclair family from Dinosaurs, "Changing Nature"

Planetary-scale Species Extinction of most complex multi-cellular organisms. Not only are humans gone, but most critters with them, leaving only a select few to evolve and refill the biosphere (or, as the name suggests, what's left of it).

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Examples:

Anime and Manga

• The premise of 7 Seeds does this. Scientists predicted that a meteorite with a diameter of several dozens of kilometers and various smaller ones were going to crash on the planet and wipe out all life and cause an ice-age.
• This is the ultimate purpose of the Millennium earl on D.Gray-Man. He plans to create another Threesome days of Darkness. The previous one was the biblical disaster known as the great flood mentioned below.
• Doraemon: Nobita and the Green Giant Legend have a race of Plant Aliens intending to unleash a Class 4 on Earth by dropping a green nuke, covering the surface of the world with plants, in retaliation for mankind's destruction on their non-sentient earth plant brothers. The film ends with those aliens actually succeeding, but thanks to Doraemon's Stop Watch prematurely activating, the gang realize the time on earth is frozen and they still have a chance to reverse the nuke.
• The prestory to Ergo Proxy destroyed essentially the entire biosphere of planet earth, though humans still managed to survive. Granted they no longer were living on Earth, but...
• Flower Girl in Dystopia: The human race was wiped out of existence after an apocalypse, presumably environmental extinction as mentioned by the gas mask man. Anthropomorphic non-humans have become the dominant species, while the flower girl is the only unambiguous human left.
• The Junji Ito short, "Hanging Balloons", where earth is taken over by mysterious alien balloons resembling human faces actively abducting their identical counterparts. The Downer Ending sees Tokyo completely wiped out by these creatures, with the main character about to be assimilated by her balloon in the last panel; a short sequel titled "Return of the Hanging Balloons" reveals the balloon creatures managed to take over the rest of Japan.
• Macross: Do You Remember Love? ups Earth's desolation to this level. In the original series, the Earth was devastated, but it was shown to be recovering several years later and there were still several million human survivors scattered about the surface. In the movie, absolutely nothing on the land has survived, although there are apparently still fish in the ocean, with the crew of the Macross being the only human beings left alive.
• Second Impact in Neon Genesis Evangelion and Rebuild of Evangelion melted the Antarctic icecap and generated tidal waves that inundated coastal regions, wiping out cities and large tracts of arable land. Simultaneously, the oceans were poisoned (only in the Rebuild continuity) and left barren and the axis of the Earth shifted. What species survived only endured due to humanity's intervention to maintain the terrestrial ecosystems. Third Impact is expected to escalate the situation to Class 5.
• Pokémon:
  • Mewtwo attempts this in Pokémon: The First Movie via a self-produced global hurricane with the eye around his island. He creates a few dozen clones of the strongest Pokemon he could get, intending to repopulate the world with human-free Pokemon. Eventually he changes his mind.
  • In Pokémon 2000, the disruption of the harmony of fire, ice and lightning starts similar world-threatening storms.
• Invoked in Sonic the Hedgehog: The Movie: the setting, Planet Freedom, is a weird blend of World in the Sky and Floating Continent, with all of the various sapient races inhabited the floating "Land of the Sky" and the planet's surface, the "Land of Darkness", being inhabited only by Robotnik and his Mecha-Mooks. Robotnik's plan turns out to be destroying the massive glacial mountain that holds the Land of the Sky to the Land of Darkness, whereupon the combination of their own anti-gravity and the planet's rotation will result in those continents being hurled out of the atmosphere and into space.
• The anime Wolf's Rain, in which the Earth's crumbling biosphere is for all appearances dying of old age, has this as a comparatively optimistic outcome. No wonder the wolves want to leave.

Comic Books

• Nick Fury, Agent of S.H.I.E.L.D. (1968): Centurius plans to kill everyone on Earth by raining down radioactive fire for forty days and forty nights, then resettling the planet from his orbital A.R.C. a century later. He's specifically trying to exterminate humanity, but it's clear his plan will wipe out many other species as well. Fittingly, when he was a normal human scientist in the 1930s, his first name was Noah.
• Superman:
  • The Supergirl Saga: Three renegade Kryptonians from an Alternate Universe do this to their dimension's Earth. The enormity of their crime drove Supes to break his non-killing oath and give them a Kryptonite shower.
  • Supergirl: In the story arc Strangers at the Heart's Core, the war between Gravitron Man and Gravity Lord's using gravity-altering devices threatens to rip the planet apart and damage the environment permanently, which would wipe out countless species, including humans.
  • Legion of Super-Heroes: In the storyline The Great Darkness Saga, the Master of Darkness takes over the minds of the whole population of Daxam and commands his three billions of slaves — every one of them as powerful as Superman — to set their homeworld on fire. Then, after the whole Daxam has been burned to ashes, he orders them to carve his face into the scorched planet.
• Suspense: In the end of Issue #14, "Death and Doctor Parker", the far-future human civilization destroys itself in an apocalyptic interplanetary war that leaves the Earth a field of ruins and craters home only to weeds, insects and the immortal main character. Over time, these survivors repopulate the Earth and transform it into a world of steaming jungles ruled by insects of monstrous size.
• The Transformers: Regeneration One: When the Autobots return to Earth, they discover that Megatron has ravaged the world with nuclear annihilation, reducing cities to ruin, boiling away most of the world's oceans and killing off much of humanity.
• Wonder Woman: The Citizenry are a spacefaring race that consumes the entire sapient and animal population of worlds.
• Y: The Last Man: Every male mammal on the planet dies, save for Yorick and his pet helper monkey and two male astronauts in space. The cause has been vague, but options include an ancient curse or a biological experiment gone wrong. The comic even mentions that, 7 months after the disaster struck, the first species has gone extinct as its reproductive cycle has flown by. It should be noted that the actual short-term effects look more like a Class 1. The looming fact that this is the last generation as far as most of humanity knows barring serious reproductive breakthroughs is anything but glossed over. Thankfully, in the Distant Finale, we see that Dr. Mann's cloning research has paid off, and it looks like humanity has made a mostly complete recovery — complete with roughly the same political problems as before — making this a Class 1 with a recovery period in the decades. In addition, even after rats should have died out with no males to propagate the species — almost five years on — some are seen on the streets of Asia, which stuns Mann.

Fan Works

• In Gender Confusion, all living creatures die within the Elemental Nations, effectively wiping out humanity because of Deidara's sacrifice. This occurs due to narrowly avoiding a Class 6 Universal apocalypse.
• Purple Days: In this A Song of Ice and Fire fanfiction, the Long Night actively threatens to systematically exterminate "ALL CURRENT SENTIENT/NEARSENTIEN LIFE" on the planet via a combination of Zombie Apocalypse and Glacial Apocalypse, using the Others (who are its "platforms") and their wights. It's revealed this has occurred dozens if not hundreds of times before the present, wiping away as many Precursor civilizations.
• In Star Wars Paranormalities Trilogy, Emperor Valkor orders Mortaqa to harvest the life force of every living creature on Christophsis except for Zolph and the Valkoran forces, just to torture Zolph by making him experience Force backlash and to give him a preview of how he's going to try to kill him (and to create a Forceless symbiote for Valkor to assimilate). However, since Emilin trying to suppress Facadma's power as best as she could spared Grein from the attack, other life forms could have been spared, and it's possible some Christophsians were off-world when the annihilation occurred.

Film — Animation

• WALL•E: While (an unknown percentage of) humanity escapes into outer space, the biosphere of Earth completely collapses, with only two living species seen in the film proper: the cockroach, and a small plant (and both seem to be very rare). It appears that no humans survive on Earth itself. The fact that human civilization does survive (in a way) aboard the starliners makes this a bit of a toss-up between Class 4 and Class 1 — but really, it's simply a case of humans fleeing from a Class 4 event.

Film — Live-Action

• Alien: It's revealed in Alien: Covenant that Chemical A0-3959X.91–15 (first featured in Prometheus) inflicts a surgically-precise Class 4 on any inhabited world that it's released upon: the artificial mutagen targets all non-botanical life, killing them outright or using them as hosts to spawn mutant hybrids. The Engineers were planning to release the mutagen on Earth in Prometheus. Before the main time frame of Covenant, David has successfully used the Engineers' own bioweapon on their homeworld's population.
• Arachnophobia. The first generation of ridiculously deadly spiders are sterile, but the spider expert points out that the second generation will be able to reproduce, which would begin as a Class 0 (the spiders kill everyone in town) but eventually escalate to a Class 4, because nothing would be able to stop the spiders from killing and eating most higher life forms on earth.
• Deep Impact: As described by the president; if the larger chunk of the split comet hit, it would've caused an impact winter which would've caused all plant life on Earth's surface to die off within four weeks, and animal life would've died within a few months.
• Don't Look Up: The main protagonists discover a comet large enough to cause an extinction event that's heading for Earth, but most of the populace is either apathetic to it or willingly ignorant of its existence. By the end of the movie, the comet hits Earth and renders humanity and possibly many other species extinct.
• Five: An atomic Depopulation Bomb wipes all of humanity (barring the five known survivors) and almost all terrestrial vertebrates (some birds are noted as having survived). Its effect on marine life and invertebrates is unknown (although the survivors manage to propagate some plants, implying the survival of some insects).
• Interstellar: In terms of the biosphere, the ongoing apocalypse on Earth has already reached Class 4 levels. At the film's start, wheat has been extinct for several years, okra is due to go extinct in less than a year, and corn will go extinct before long. It's projected that the end result will be the extinction of all plant and animal life on Earth
• Marvel Cinematic Universe:
  • Avengers: Age of Ultron: Ultron intends to inflict an extinction event on the Earth, first by launching all nuclear bombs (what remained of Jarvis blocked him, and then Vision took Ultron off the internet to be sure), and ultimately turning Sokovia into a Chicxulub-like impactor for a Colony Drop. He at first indicates he wants to push humanity to evolve and improve, but his reasoning is Insane Troll Logic at best with his fractured mindset. Friday states when Ultron is enacting his plan that the blast will likely wipe out all human life around the world, and after losing Vision, Ultron implies he'll probably try to inflict a Class 5 so that he's the only thing left alive.
  • The fate of Thanos's home planet Titan was somewhere between this and a Class 6, as revealed in Avengers: Infinity War. Thanos claims that an Overpopulation Crisis caused the extinction event, but Peter (Quill) notes that the planet itself is off its axis and that gravitational pull is "all over the place", indicating that a lack of resources wasn't the only reason for Titan's demise.
• MonsterVerse: Although the MUTO crisis in Godzilla (2014) is presented as likely being a Class 2 if the giant creatures successfully reproduce, the Godzilla: Aftershock comic indicates the species would've actually caused a new extinction event due to them destroying or reshaping entire ecosystems.
• The Quiet Earth, film version. The vast majority of the Earth's animals were affected by the Event and disappeared, up to and including most humans. The cause of it was human-engineered, but the fact that animals were also affected pushed it from Class 3 to Class 4. Plants were completely untouched, however.
• Reign of Fire: The biosphere has suffered this due to the dragons (who were responsible for wiping out the dinosaurs during their previous active cycle) scorching all the lands to ashes for them to consume. Humans' Nuke 'em actions against the dragons before society collapsed likely helped.
• Heavily implied in Resident Evil: The Final Chapter as a direct result of the worldwide T-Virus pandemic. There's no plant life to be seen anywhere, virtually all animal species have been turned into undead monsters, and the scattered remnants of humanity count less than 5,000 souls — far too few to sustain a genetically viable population in the long run even with the T-antivirus killing off the mutants. Umbrella may be destroyed, but it happened too late, and it's only a matter of perhaps a century until Earth is left as nothing but a desolate wasteland devoid of life.
  • There is still hope though — in Afterlife Alaska is shown to have retained much of its biosphere. If survivors settle there, they may have a chance of survival.
• The Thing (1982): The Assimilator alien organism is liable to cause this with certainty, and more than likely a Class 6 to Earth's biodiversity, if it ever spreads outward from Antarctica.
  PROJECTION:
  IF INTRUDER ORGANISM REACHES CIVILIZED AREAS...
  ENTIRE WORLD POPULATION INFECTED 27,000 HOURS FROM FIRST CONTACT.
• Van Helsing: this is implicitly what Dracula's plan will lead to. It's mentioned early in the film that Drac and his brides just kill one or two people a month from the single Transylvanian village that they live near, which is obviously bad for the people living there but nothing especially serious on a global, continental, or even national scale. Then it turns out that there's several dozen "stillborn" vampire children in his base near the village and they're momentarily unleashed before magically exploding because he hasn't yet figured out how to give them lasting life. After this, it's revealed that there are thousands of them in Castle Dracula, and if they get out and acquire lasting life then that will almost certainly lead to the total extinction of mankind.

Literature

• Alien Earth by Megan Lindholm, in which a large group of Humans were rescued by aliens, just prior to the total collapse of Earth's ecosystem. What's left is mostly inedible to these humans, being mostly ground hugging bushes.
• Scenario #8 in John Scalzi's Alternate History Search Results studies what would happen if Hitler had been killed in 1908...by hitting him with a meteor. Humanity and 93% of all species on Earth are killed off as collateral damage.
• According to The Bible, a Class 4 catastrophe occurred some 4400 or so years ago, with a global flood wiping out nearly everything except for a wooden supertanker-sized boat filled with animals and a human family.
• The hallucinogenic fungus in Child Of Earth ends up spreading to all organic matter until the mold growth is all that remains, having become the titular Child of Earth. (It's also speculated by characters that the lifeform first came to Earth as a remnant of a Class X event elsewhere in the universe.)
• The Count of Monte Cristo: Discussed. A depressed Caderousse discussing humanity's evil, and saying that sometimes it'd be better if it rained two days of powder and an hour of fire.
• Roger Zelazny's Damnation Alley is set post-nuclear apocalypse. Most of the surviving population are in coastal cities, while those remaining in the Midwest blame scientists for the catastrophe, and crucify any they catch. There is animal life, but not as we know it.
• In Down to a Sunless Sea, the last nuclear war wipes out almost everyone, except two planeloads of people, who have to run to Antarctica to start over, then they discover that the nuclear weapons have knocked the planet off its axis, meaning that Antarctica is soon going to be in the tropics. Depending on which ending your copy has, either it's the end of the world at which point God steps in to begin all over again, with the last two human survivors the new Adam and Eve, or they will go out to rebuild the world.
  • Mao Zedong apparently gave serious thought to having a few 747s full of Chinese citizens in the air at all times, to provide for just this situation. (In practice, the shockwaves from a global thermonuclear war would likely knock these aircraft out of the air, so it probably wouldn't work.)
• Dream Park: The Fimbulwinter Game, played out at Dream Park in The Barsoom Project, depicts the near-total freezing of the planet by a crazed Cabal of Inuit sorcerers. Only Arctic natives and organisms have any hope of surviving, and it's hinted that the Cabal's rituals may have overdone it, potentially pushing even these into extinction (and this example into Class 5).
• In The End and Afterwards, the impact of Star Pioneer is a 4.5. Human extinction is not immediate, but nearly certain within 50 years. Much, perhaps most of the biosphere is equally doomed. Humanity itself survives, but only by escaping to Alpha Centauri.
• Flanimals: Day of the Bletchling ends with the titular monsters wiping out all other Flaniamls on the planet in an apocalyptic war, in the process also dooming their next generation to starvation. But by the end, it's revealed that some microscopic sploon is still around and there's a possibility it could evolve to repopulate the world with new Flanimals.
• The Future is Wild: In the year 100,000,000 A.D, a series of volcanic eruptions start a severe mass extinction that kills off out most lifeforms, including all tetrapods, leaving fish and invertebrates, such as molluscs, insects, and polychaete worms, to inherit the world left over.
• In The Green Gods, massive amounts of climate change caused plants to evolve sapience and begin taking over the world. Many animals, including humans, are on the brink of extinction.
• Fiery Tail from Harda Horda anthology is a near-textbook case of a mass extinction event caused first by an entire swarm of asteroids hitting Earth, and then the resulting ice age wiping out most of the things that managed to survive the impact event. In the unspecified future, when human survivors return from their Space Arks to resettle the planet, the biggest mammals on the surface are mouse-like rodents, and for all intents and purposes, Earth is a virgin planet without a single trace of anything even resembling civilisation. The story toys with the idea that someone might have survived, but they didn't find from orbital surveys anything that suggests even traces of permanent human settlements, implying humanity on Earth died out entirely, if not thanks to the impact event, then the following ice age.
• Line of Delirium describes the destruction of the Sakras: the human Empire went for planet-wide meson bombardments on all planets that belonged to the Sakras race or were about to be conquered by them. Technically a Class 6 for those Sakras on the receiving end, the bombardment burns the atmosphere and boils the oceans. Several decades later a human refugee remarks that there is hope for her homeworld — the oceans are about to stop boiling and the planet might be repopulated. The genocide of an entire race is unique in the books, and frowned upon by other races in the games, but repopulating and terraforming planets which were previously rendered sterile is par for the course. It is possible to win the game by becoming the only remaining sentient species.
• The conclusion of Man After Man: An Anthropology of the Future finds the Earth almost totally stripped of life by the evolved, no-longer-recognizable descendants of human space colonists. Its contaminated atmosphere no longer supports any organisms, and only a handful of native species survive, clinging to deep-sea hydrothermal vents.
• In The Mote in God's Eye, the Earth is a radioactive wasteland kept as a military training preserve by the Empire of Man, as a lesson to all young officers in the Imperial Fleet "to show them what the Empire exists to prevent." The only places on Earth that can support life are the high mountaintops (ironically, some Jamaican Blue Mountain coffee plants have survived the Apocalypse, and they've all been declared the private property of the Emperor for his exclusive use. Smart Emperor...)
• On the Beach showed humanity completely dying out after a large-scale nuclear war. In the book, it's discussed that dogs, mice and rabbits, being more resistant to the spreading radiation, will outlive humans, but even the rabbits won't last more than a year or so after.
• In The Purple Cloud, the titular Fog of Doom wipes out most human and animal life on the planet. The only survivors are some aquatic animals and insects, a man on a polar expedition who is farther north than the cloud reaches, and a young girl in an airtight cellar.
• In The Fractal Prince the Sobornost mind-upload collective has purged most of Earth's surface from life after uploading perfect copies to their giant databanks, and a Grey Goo-nanotech called Wildcode did the rest. Only one city, ironically protected by the Wildcode, still has baseline human population. By the end even it's gone, after Matjek Chen unleashes the Dragons, an even more destructive Grey Goo weapon, on the planet in order to retrieve a copy of his past self. In subversion, upload copies of people continue to live in the Wildcode itself until Chen's purge. Amusingly, the sequel novel, The Causal Angel reveals that the catalyst for all these events was a deliberately engineered planetwide stockmarket crash.
• In Fragment, a reality TV show crew discovers a teeny, tiny landmass (only about two miles wide) in the middle of the Pacific Ocean known as Hender's Island. They subsequently then discover why no else has discovered the island before: the entire native ecosystem is a horrible eternal orgy of violent dismemberment and splattering death where the food chain breaks down and everything eats everything. As it turns out, the island is a lost fragment of an ancient Precambrian supercontinent, and as the island got smaller over millions of years, the competition got ever more intense until it became a maelstrom of constant slaughter where the trees drink blood, the grass sprays acid, and the bugs are biological Grey Goo. The characters calculate by computer simulation that if even one organism from Hender's Island reached the mainland, life on all inhabited continents would be wiped out within forty years at the most. Only those living on remote islands might be spared, because as it turns out Hender's Island life-forms are deathly allergic to salt water.
• Last and First Men: The Late First Men accidentally manage to chain-detonate massive amounts of radioactives in situ underground, causing massive volcanic eruptions that nearly wipe out all animal life on Earth. Earth life only survives in a few isolated areas, mostly in the Arctic, where humanity hangs on through twenty-seven survivors. All future non-alien creatures in the series descend from these humans and a handful of arctic animal that survived the devastation.
• The Night Land is set "billions of years hence", after the Sun has died (although that should have incinerated Earth). Humans have only survived by sealing themselves inside The Last Redoubt, a massive city inside a pyramid. No one can live in the outside world without special suits. The only things living outside are Eldritch Abominations that have colonized the Earth.
• In The Riftwar Cycle by Raymond E. Feist, Kelewan gets this, not once, but twice. In the same book. First it starts getting swallowed by an ever-expanding portal to what amounts to the second circle of hell, powered by the deaths of the army trying to stop it. Then, to put an end to that threat, Pug created a gigantic rift portal that basically slammed a large part of Kelewan's moon into its surface at extreme speed. Luckily, a good part of the population escaped to another world.
• In Sea Of Rust, mankind, along with many other species, are extinct after a global war between mankind and robots. Its prequel, Day Zero, shows what happened on the first day of said war.
• We Are Legion (We Are Bob): When the Brazilians fired on the HEAVEN-1, this started a war. Every nation got involved, and China eventually destroyed Brazil by dropping asteroids on them. Riker and Homer arrive just as the last Brazilian warships are preparing to drop asteroids on what's left of China, which would render the Earth uninhabitable in weeks instead of decades. Once the warships are dealt with, Riker works to evacuate the fifteen million survivors, since it will take ten thousand years for Earth's biosphere to recover.

Live-Action TV

• Alien Worlds (2020): This is implied to happen at the end of "Atlas" after a meteor impact compared to the end-Cretaceous mass extinction. The effects aren't shown, but the narration states that highly specialized animals like the skygrazers and their predators will be unable to cope with rapidly changing conditions and the loss of their food sources and will go extinct.
• Babylon 5 has the Vorlon planet killers. These planet killers are more likely to be around Class 3-4 — one episode has Ivanova requesting atmospheric shuttles to evacuate survivors from the surface of a world devastated by the planet killer. It doesn't destroy the planet, but once it strikes, it's curtains for most of the population, and the few who remain will probably slowly die of starvation, disease, radiation poisoning, or the like unless they are rescued.
• Buffy the Vampire Slayer: The opening of the Hellmouth is a 4.5. It would release demon hordes onto the Earth, resulting in the extinction of every species on Earth, whose natural biosphere would be replaced with a demonic one. This is prevented four times, in the episodes "The Harvest", "Prophecy Girl", "The Zeppo", and "Doomed". The release of the First's army of Turok-Han, as averted in the series finale, would apparently have a similar effect.
• The Creepshow episode “Gray Matter” ends with Timmy’s drunken, widowed father Richie having mutated into a self-duplicating Blob Monster, with the heavy implication that he and his spawn, with their voracious bloodthirst, will bring about mass extinction in just six days.
• The final episode of Dinosaurs. Earl Sinclair unwittingly engineers a series of catastrophes that causes the extinction of all plant life, and eventually dinosaurs with it. But the scale is so far beyond what really happened to the dinosaurs, it could go beyond even Class 4 on the Apocalypse How scale.
• Doctor Who:
  • "The Ark in Space" and "The Beast Below" mention disasters where enormous solar flares roasted the Earth, which are probably the same event. Humanity may well recover (they had warning and were able to evacuate), but the biosphere is implied to be long gone.
    • "The Sontaran Experiment", the adventure following "The Ark in Space", takes place on Earth directly after the events of the previous serial (the Doctor and companions having used a transmat to reach the surface). There is a well-established biosphere and a perfectly reasonable climate.
  • "Gridlock": From what Novice Hame says, it sounds like The Plague which wiped out New Earth's population save for herself, Boe and those sealed in the Undercity didn't just affect the sentients but also the entire biosphere outside of the Undercity, thereby making the overall fallout a Class 4.
• Game of Thrones: The White Walkers bring winter storms wherever they go, the show's last few seasons imply the Walkers' mere presence is responsible for transforming the once-green Lands Beyond the Wall into the subarctic wastes they are today and keeping them that way, and their master is an Omnicidal Maniac who seeks to more or less Kill All Humans while erasing everything in the world that makes humanity distinct. With all this in mind, it's likely their Zombie Apocalypse's success in the Seven Kingdoms would spell at least Multiple Species Extinction on a Continental scale, with the Army actively eradicating humans and with their Endless Winter causing an ecological catastrophe for other animals and plant life. And once the undead are finished erasing Westeros, who's to say they won't turn their eyes to the remaining continents, especially after they acquire an undead dragon that can fly them across the Narrow Sea...
• The virus that wiped out humanity in The Last Man on Earth apparently wiped out all land-based vertebrate life, at least. There are no cats or dogs or birds to be seen, Carol makes a random comment about how meatballs are a thing of the past, and the gang is shocked when they find a random cow. The fate of non-vertebrates (bugs, worms, etc) and marine life is unclear.
• Power Rangers RPM starts with at least a 1.5, but by the end of Ziggy's first scene, it's clear that it's really a 4. Yes, this takes place on Earth.^note An alternate Earth, we later find out, but still. In Power Rangers. Its strongly implied that the means by which the Venjix Virus razed the planet was nuclear carpet-bombing.
• Primeval: In the depictions of the Bad Future. In Season 3, it superficially looks like a Class 2-3a has occurred with forests growing below cliffs and multiple future species existing, but Helen Cutter heavily implies the destruction was actually Class 4. The show's last two seasons depict a Bad Future where a severe Class 4 in the present has turned the future Earth into a nigh-inhospitable Death World that's hurtling towards Class 6 extinction.
• The War of the Worlds (2019): After the Alien Invasion, although human survivors still exist (for now), the Martians' red weed has overrun and severely choked all of Earth's native ecosystems, which has the potential to climb into a Class 5 for Earth's native life. However, the Hope Springs Eternal ending suggests that with the right conditions to kill off the weed, Earth's native biosphere can start recovering.

Tabletop Games

• In the Dungeons & Dragons Splat book Elder Evils, this is the most likely worst case for four scenarios:
  • For the Sertrous scenario; should the heroes fail, the game world's ecosystem would remain unharmed, but most humanoid races would be rendered extinct and replaced by Sertrous' reptilian and demonic followers.
  • For the Hulks of Zoretha, failure will mean the awakened Hulks beginning a campaign of extermination against all sentient beings on the game world who could possibly compete with their horrific offspring; the Blood Moon sign throughout the whole campaign might result in a Class 1 anyway, given the Hate Plague it causes.
  • Leviathan's scenario would cause whole continents to sink into the sea, destroying civilized areas; the ecosystem would mostly survive, but not much else. In fact, by the time its Sign reaches Overwhelming (right before the Final Battle) a Class 1 has already occurred, but hope for recovery remains should the heroes defeat the beast.
  • Worst case scenario for the Ragnora would make the world better suited to support life in general, but the corrupted positive energy caused by the abomination would be "too much of a good thing", causing most species who didn't die from it outright to mutate into horrid, mindless, pseudonatural beings.
• In Rocket Age Mars and Io have faced Class 4 level events.
• Tech Infantry has a meteor impact do this to the planet Earth, although it is eventually resettled by humans and other life from colony worlds. Then it later gets destroyed in even more spectacular fashion.
• The Exterminatus operation in Warhammer 40,000 is an attempt to destroy a planet as an economic or military asset. Depending on how thoroughly it's carried out, it usually ranges from Class 4 to Class 5, but can go all the way to X if they really try. If the bombardees have particularly deep bunkers or the bombardiers get sloppy, this can be as low as Class 2, as in the case of Tallarn (Single-Biome Planet turned from lush vegetation to desert Death World, but still inhabited).

Video Games

• Fate/Grand Order has one of these in the backstory of the British Lostbelt. In Proper Human History, the alien giant Sefar arrived on Earth and caused a Class 2 apocalypse before ultimately being stopped by a Precursor Hero wielding Excalibur. However, in this Lostbelt, the faeries that were responsible for forging Excalibur opted to slack off instead, which allowed Sefar to rage across the planet unimpeded. By the time they woke up, the faeries found that the surface of the planet was so thoroughly destroyed that all that remained was an endless ocean, while humanity and the gods (except one) were all extinct. This laid the groundwork for The Fair Folk to become the dominant species in that particular Lostbelt, rather than humans.
• Earth freezes over in the backstory of Frostpunk, causing the deaths of nearly every living thing on the surface. Causes are attributed to solar dimming and ash thrown into the upper atmosphere from several large volcanic eruptions and a meteor strike. A few thousand hardy people stake out territory in coal-rich areas, set up massive steampunk thermal generators, and try to survive until whatever caused the Great Frost passes. Food comes from hunting what few animals or growing whatever simple plants could survive the initial deep freeze.
• In Knights of the Old Republic the planet Tatooine use to be a beautiful habitable world, then it was bombarded by the Rakata turning it into the desert world it is now, the few that survived were the Tusken Raiders.
• The event that kicks the prequel of Outpost 2 is the impact of an asteroid nicknamed "Vulcan's Hammer" on Earth with the force of 1 billion megatons,^note For the record, this is 10 times the force of the Chicxulub event after the attempts using nuclear weapons to divert its trajectory failed and simply caused it to break in two pieces.
• Pokémon:
  • Pokémon Ruby and Sapphire: Stated to be the end result of Groudon or Kyogre awakening and seizing total power for themselves. Kyogre would drown the world in a torrent of neverending rain, while Groudon would burn the surface into a bone-dry desert. Fortunately, not only are they in opposition to each other and evenly matched in strength, Rayquaza has been known to descend and force them into hibernation whenever they do start fighting.
  • In Pokémon X and Y, Team Flare attempted to use a Doomsday Device to end all human and Pokemon life on Earth (save for themselves and their Pokemon) in order to remake the world in their image.
• Shantae: Risky's Revenge: The rant of the chef girl in the Forest if you refuse to give Wobble Bell back, ends with her talking about how not giving Wobble Bell back would lead to The Famine to end the world:
  I'll give up cooking and the world will have nothing to eat, and every living thing will starve and die out. The land will grow cold and life as we know it will cease. Oh Wobble Bell, please come back.
• In SOMA, this is the result of the comet Telos hitting the Earth. All life on Earth's surface is killed, but marine life remains unaffected.
• Splatoon:
  • This is part of the backstory for the series. Humans and nearly every other non-aquatic animal were slowly wiped out by a combination of climate change and constantly escalating thermonuclear war, culminating in a stray warhead hitting Antarctica during World War V. Aquatic creatures evolved to live on the remaining land in the millennia following mammalian extinction, with Judd (a genetically modified cat) being the only living mammal in existence until the second game quietly introduced his clone. Meanwhile, remnants of humanity still exist, from ruins of landmarks like the Eiffel Tower, to reflected radio wave messages that serve as the basis for the games' Splatfest events, to even a crashed Colony Ship.
    Pearl: I went digging in my backyard earlier today, and I found some old bones!
    Marina: Human bones, huh? Yeah, those things are everywhere.
  • Splatoon 2: Octo Expansion ends with the player character and their allies having to prevent one of these. Commander Tartar, a human-made AI created during humanity's last days with the intention to pass humanity's knowledge to the next dominant species, decides that none of the various species that have emerged are deserving of it; this is due to his view that Inklings and Octarians fighting against each other replicates the same kind of conflict that doomed humanity. As such, they aim to turn every creature on the continent into primordial ooze in hopes that the next round of sapient life meets their standards.
  • Splatoon 3 takes it a step further with Mr. Grizz, who intends to use the Fuzzy Ooze he's tricked the inklings and octlings into gathering for him under the guise of a business. The final boss has you taking him on in space as his fuzzy ooze-filled missile intends to strike into Earth. Doing so will coat it in the ooze, turning every marine animal into mammals, and likely killing the vast majority of them instantly. He knows this and sees it as necessary to reinstate mammals as the dominant life on the planet.
• In Subnautica, the gigantic crater in which the game takes place is the only location on the entire planet which still has life. Everything beyond the crater is dead zone where the only life is either microscopic or very very large and hungry. This is because of a killer plague that the Neglectful Precursors unwittingly unleashed into the world and the Sea Emperor Leviathan distributing small doses of curative enzyme through Peepers and alien vents.
• The oldest semi-confirmed event in Touhou Project backstory is the creation of Heaven (lit. Celestial World). It occurred by removing a massive Keystone from the Earth, devastating the surface and destroying everything. The good news is that this happened so long ago that even Eirin Yagokoro had not yet been born, so it's a good possibility that very little death occurred.
• The Armageddon spell in Ultima, which is described in the fluff as destroying all life in the world, and when actually cast instantly kills all NPCs. Depending on the game, there may be two or three survivors, usually the Avatar and Lord British.
• In Xenoblade Chronicles 1, Zanza, the soul of Bionis, causes this whenever his civilization grows advanced enough to leave his body as without ether (i.e. life energy) from living organisms, he would die.

Webcomics

• This happens in Deviant Universe during the Dark Future storyline.
• Homestuck: After Her Imperious Condescension took over Post-Scratch Earth, she turned it into a Crapsack World and caused the collapse of civilization and a series of holocausts, eventually just flooding the planet. This should have wiped out most of Earth's biosphere, but apparently some life still survived. This, however, is only true because she was instructed to do it all by Lord English, an omnipotent and practically omniscient being of destruction.
• Rash Illness in Stand Still, Stay Silent attacks only mammals (except for cats), turning them into trolls (humans), beasts (animals) giants (Body of Bodies), and general Body Horror. Seeing how only about 11% of population is immune (probably less at the start of the Illness), it killed most of mammal and human life on Earth, leaving only few scattered remains.
• In White Noise, the invading aliens temporarily halted the Earth's rotation, which caused everything not directly attached to bedrock to be thrown into the atmosphere and the air itself to ignite due to the massive friction. They then tried to the planet to suit their needs, but this didn't take. Life was only able to return to the planet because humans had three orbital space colonies to repopulate from. The Earth is presently habitable, but only by a very generous application of the word habitable.

Web Original

• The Jenkinsverse sees the alien planet Cimbrean facing a Biosphere Extinction after an unwitting human traveller innocently (and unavoidably) contaminates it with their gut flora when they answer a call of nature. Cimbrean's biosphere has no way of defending against these organisms, which proceed to go mad, spreading at an incredible rate and digesting all organic matter as they go. By the time anybody notices, the contagion has progressed beyond the point where it could be contained, and the only hope of preventing Cimbrean from becoming totally uninhabitable is to import Terran life forms to replace the doomed natives.
• Episode 14 of Alien Biospheres features a mass extinction occurring on the planet Tira where the series is set, which kills off most of the planet’s multicellular life, as a direct parallel to many of the mass extinctions on Earth.
• Rooster Teeth series, Day 5 has this with it seems all animal life. Anything that can fall asleep dies in its sleep. The story is set 5 days after the event with the few people who have managed, depsarately to stay awake while trying to find answers.
• Serina: The mass extinction separating the Thermocene and Pangaeacene periods sees 99% of all life wiped out by runaway global warming and ocean hypoxia, leaving only a small sampling of species in one habitable zone to repopulate the entirety of the world.
• S. D. Locke's proposal for SCP-001 has the sun into a red star that causes all life its light touches to melt into Blob Monsters.
• Kurzgesagt explores this in a video that poses the question "What If We Detonated All Nuclear Bombs at Once?" With all the nukes currently in existence, the Amazon rainforest where the nukes would theoretically be detonated would be razed and South America would get rocked hard, but aside from some small climate changes, nothing world-ending. If we made nukes with all of the known Uranium in the world and set them all off at once in the Amazon? EVERYTHING DIES! South America is practically gone. Raining debris from the explosion sets off wildfires the world over. Seismic shockwaves flatten cities. Dust and aerosols from the explosion block out the sun, creating a deadly nuclear winter that will kill off most species, including humans. The entire planet is also irradiated, although very few creatures will be alive to suffer the effects of radiation poisoning.

Western Animation

• Final Space: Season 3 reveals that Earth has suffered this after being dragged into Final Space at the end of the first season. The planet is overall intact if without its sun and heavily poisoned by Final Space, and besides Kevin Van Newton and the KVNs who survived the apocalypse, there are even mutant beasts on Earth who mutated into monsters instead of dying.
• Jackie Chan Adventures:
  • Tso Lan however threatens to at least cause this, possibly even a Class 5, as he wants to pull the moon from orbit and wreck all of Earth's ecosystems as Hostile Terraforming.
  • In Season 5, Drago intends to bring Hell on Earth. In his Storyboarding the Apocalypse, though humans are still around it looks like it'll logically be a Class 4 for the Earth's biosphere — the moon is broken in two and extradimensional demons are roaming.
• The Secret Saturdays: In "The Atlas Pin", the Nagas threaten to cause this by pulling the titular pin out of its place between the tectonic plates, which would cause a global earthquake chain severe enough to rip apart the continents.
• Transformers: Prime: Before the series' main time frame, Cybertron was rendered a dead planet for all intents and purposes due to Megatron's Planetary Core Manipulation corrupting the planet with Dark Energon. Cybertronians can still walk and breathe on their home planet, but the planet's systems have stopped producing life-giving Energon entirely, which forced a Homeworld Evacuation. Despite this, Scraplets and Insecticons still inhabit Cybertron's ruins in the present time.

  • At the end of Season 3, after Cybertron's core is successfully restored, Unicron attempts to fully reverse this by re-corrupting the core with his Dark Energon.

• Wakfu: At the very least, Qilby draining the World of Twelve of its wakfu to power the Zinit would cause this (possibly higher), with the planet being stated to have "just enough" wakfu to get the Zinit off the ground. The guy insists the world won't be destroyed though, it'll just be a bit, erm... ravaged.

Real Life

• Mass Extinctions (events of this scale) have happened several times in Earth's history:
  • The Great Oxygenation Event, in which the appearance of oxygen in the atmosphere resulted in the death of many anaerobic multi-cellular organisms.
  • The Ordovician-Silurian Extinction was probably caused by natural climate change, and killed 60-70% of all species.
  • The Devonian Extinction, caused by more natural climate change (possibly triggered by one or several meteor impacts, or the evolution of plants), wiped out 70% of all species on Earth.
  • The Permian-Triassic Extinction was by far the most destructive, killing 90-96% of all species on the planet. (Even scientists not given to sensationalism call it "The Great Dying") There are several possible causes, including asteroid impacts, increased volcanism, release of methane, or some combination of the above.
  • The Triassic-Jurassic Extinction was probably caused by more climate change, and killed 70-75% of all species.
  • The Cretaceous-Paleogene (earlier known as Cretaceous-Tertiary) Extinction is the most famous. Probably caused by an asteroid impact though climate change and mass volcanic eruptions may have also played a role, it killed 75% of all species, including the non-avian dinosaurs, large marine reptiles, and pterosaurs.
  • Humans are seemingly in the process of causing another one, but how serious it gets depends on our actions.
    • Actually, the current (relatively minor) extinction process had been going on for a while. Lots of species of large mammals have been lost in the past 50-80 thousand years. And while humans are most likely part of the reason for the extinction, there is also climate change (no, not the one we have been causing since the 20th century) and the apparition of new diseases are also to be blamed.
• Global nuclear war could leave the world safe for cockroaches... At least for a while, given that cockroaches survive off of waste provided by greater beings. When they're gone, the roaches would be living on borrowed time.
  • More specifically, the most pessimistic predictions of a nuclear war would see the planet's biosphere basically collapse, resulting in a global extinction event that would likely render most multi-cellular land dwelling species extinct. This is because even small changes to the planet's carefully balanced biosphere can produce horrific results, such as crop failures and resulting famines, and while humanity in its current state could likely counter-act many of these problems at great cost, the destruction of most of human civilization from a nuclear war would make it almost impossible to artificially combat the biosphere collapse.
• There were rumors of a close call during the 1990's when a German biotech company created a genetically modified root bacterium called K. planticola (since reclassified as R. planticola) that was supposed to increase the rate at which plant life decomposed into ethanol. Some researchers at the time claimed that they found in a test that the amount of ethanol produced would be fatal to almost every plant on Earth if the bacterium ended up in the wild. For that reason they published a paper, and thanks to that paper the USFDA stopped approving field tests with the modified strain of the bacterium. It would later turn out that the ethanol concentration was too low to be a significant threat to plant life, that the research was not in fact published (or apparently even submitted for peer review), that the USFDA has not been approving such field tests at all, and that the modified bacteria may not have been viable in the wild anyway (let alone able to spread globally). The researchers have retracted their claims and publicly apologized, but the myth persists.
• This will inevitably happen in a billion years from now (albeit slowly), starting with the oceans evaporating and ending with a Runaway Greenhouse.
• Discussed and averted: while working on the Manhattan Project, Edward Teller brought up the possibility that the team's work could cause runaway nitrogen fusion in the atmosphere, roasting all life on Earth. They did the math and determined that the bomb would have to be 100 times hotter to cause Teller's predicted effect.

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