Apocalypse How/Class X-2

Star System-scale Physical Annihilation. You know that big ball of hydrogen/helium fusion and the bunch of rocks that used to circle it? Yeah, they ain't here no mo'. This usually happens due to that particular fusion ball doing something unpleasant like going supernova.

Anime and Manga

 * When Cell of Dragon Ball Z launches his final Kamehame Hadoken, he claims it has enough power to destroy the entire solar system. Since he's derived from a being that can both survive in the vacuum of space and live through a planetary explosion, it seems like he could pull it off.
 * Gall Force featured the System Cannon, a Wave Motion Gun disguised as a Planet. Its primary purpose was, after the enemy was lured into its system, to would fire at its own star, blowing the entire system to space dust. Considering that its destruction formed our Asteroid Belt, perhaps it's for the best that it didn't hit the target.
 * Galaxy Express 999 has the metallic humanoids who blow up the sun to eliminate the earth because they hate and fear humans. Fortunately there are still many human colonies across the galaxy, and they are all extremely pissed.
 * In Hellstar Remina, one of the early warning signs that the titular "planet" Remina could be a problem is that nearby stars start disappearing.
 * In Hellstar Remina, one of the early warning signs that the titular "planet" Remina could be a problem is that nearby stars start disappearing.

Comic Books

 * In The Dark Phoenix Saga, Dark Phoenix recharges herself by consuming D'Bari sun, causing it to go supernova and annihilating a planet of five billion people.

Films -- Live-Action

 * Star Trek Generations has Dr. Tolian Soran blowing up suns to alter the course of The Nexus.
 * Though we don't see it all on screen, the stellar cataclysm that destroyed the planet Romulus and set Nero on his Roaring Rampage of Revenge in the 2009 Star Trek Reboot would count. This was an averted X-3, according to, however, Romulus' system is the only one known to be affected.
 * Transformers: Revenge of the Fallen: The Fallen actually wants to destroy the Solar System by using a powerful machine located within the Pyramids of Egypt that is pointed at the Sun. Fortunately, Optimus Prime destroys the machine before it activates, and later kills the Fallen by yes, tearing off his face.
 * Sunshine is about a space mission to avert this trope and prevent the Sun's imminent collapse, apparently through natural processes.

Literature

 * The Star Wars Expanded Universe featured some pretty badass weapons, ridiculous as they were, including the Sun Crusher (which caused a sun to go nova, which would result in not only its own destruction but that of any system of habitable planets it may have maintained), and the Galaxy Gun, which can blow up planets anywhere in the galaxy, without having to the leave the safety of the Empire's most heavily defended world. There's also the innocuously named Centerpoint Station, an ancient superweapon whose functions had been long since forgetten...until it was discovered (by the Big Bad of the story, naturally) that like the Sun Crusher, it can cause stars to go nova, along with other less directly destructive but still incredibly useful functions.
 * Lampshaded and parodied in Destiny's Way by Walter Jon Williams, in which Han Solo ridicules the proliferation of super-weapons (and by extension the authors responsible for giving every new Expanded Universe novel in The Nineties a new superweapon-of-the-week).
 * In Frederik Pohl's novel The World at the End of Time war between plasma-based beings that live inside stars results in the destruction of uncountable solar systems. The war is fought by directing energies into a star that tear apart the beings. It has the side effect of causing the stars that the beings inhabit to go nova. That side affect is used to exterminate biological entities before they might threaten the beings. One notable example is the destruction of a Wolf Rayet type star when one being tricks another into believing that is the type of star he prefers.
 * In the book series Into the Looking Glass, by John Ringo, at the end the hero is given a device of unknown functionality. Using the "Looking Glass" portals (so named for resembling a mirror from one side) the device is taken to an uninhabited star system for testing. After the testers return to see the results of the test, they find the entire star system just plain gone. Later books include a space station made by precursors that controls the entire output of a sun.
 * David Weber's Empire From the Ashes series has spaceships the size of moons with black-hole-generating engines that if used too close at too high a power setting to a sun, can cause it to go nova. In the third book of the series, they figure out how to micro-miniaturize the nova effect into a gravitic bomb that's less than nine feet long.
 * In Alastair Reynolds Revelation Space trilogy, the Inhibitors build a device called a star-singer. It turns manipulates the gravity of a star to turn it into a giant flamethrower, both utterly incinerating all life on the targeted planet and turning the star into a dwarf too dim to allow any life to ever evolve in that system ever again.
 * is stated to eventually cause a X-3 and then X-4 event. It is stated that  will cause the.
 * In Randall Garrett's short story "Time Fuze", Earth's first expedition to Proxima Centauri arrives just in time to watch the star go nova a few billion years ahead of schedule. It turns out that it was caused by the FTL drive on their ship; on the return trip, they discover that they accidentally blew up our own sun on exiting the solar system, too.
 * In Lensman, using planets grabbed from a universe where the laws of physics are different from ours, mainly that superluminal inertial motion is the norm rather than impossible, one is fired into a sun causing it to go nova.
 * Peter F. Hamilton's Nights Dawn trilogy has Alkad Mzu's Alchemist, which freezes a gravitational distortion node in time just before it reaches the point at which it would push itself out of the universe (many of these in a lattice around a ship are their method of FTL travel). It has two settings, one which, when fired into a star, will suck all the surrounding matter into it and create a neutron star. The lower powered setting is much more destructive, as the gravity isn't strong enough to overcome the explosive force of collapsing a star/gas giant. Which they use in order to destroy about two ships.
 * Isaac Asimov's The Gods Themselves is about a power source which, if not stopped, will cause this to happen to the Sun... and start a chain reaction bringing the catastrophe to just below Class X-3.
 * Alan Dean Foster's Humanx Commonwealth series novel The End of the Matter is about a rogue black hole that threatens multiple star systems by devouring their suns, leaving them barren and lifeless. The protagonists spend their time looking for a Lost Superweapon reputed to have been developed by an ancient race specifically for use against this type of threat.
 * One group of human survivors in The Killing Star
 * One of the many names of the Lone Power from the Young Wizards series is "Star Snuffer", since It has the ability to both render a star dark and cause it go nova.

Live-Action TV

 * Stargate SG-1's Samantha Carter drops a stargate, opened onto a black hole, into a star, causing the star's mass to be depleted and explode, destroying the Big Bad's fleet, and
 * Which makes no sense whatsoever, given that long-lived stars have low masses, while hypergiants have a life-span of one or two million years.
 * Likewise, Rodney McKay from Stargate Atlantis managed to destroy almost an entire solar system by mistake. Five-sixths, but it's not an exact science. Destroying a solar system rarely is.
 * Rodney doubtless also still resents the fact that Carter gets mad props for deliberately blowing up an entire star system, where as he only gets mockery for accidentally blowing up most of one...
 * Andromeda: The Systems Commonwealth, the good guys of the series had Nova Bombs, explosives with enough power to make a star go supernova. Dylan Hunt, the main protagonist, had 40 of them on his ship, which he used to temporarily turn a black hole into a white hole in the first episode. Later on in the series, we find out he's making more of them, though he's making them to destroy the Magog, the series' galaxy eaters.
 * In Star Trek: Deep Space Nine, Changeling-Bashir attempted to cause Bajor's sun to go supernova.
 * In The Next Generation a weapons-dealing robot is encountered whose masters died out after their sun went supernova and a Dyson sphere is discovered that was abandoned for similar reasons (in "Relics").
 * Battlestar Galactica, believing that fifteen known cases of Class 2 by the middle of the third season was not enough, gave us a supernova at the end of "Rapture". This was a natural event... maybe.
 * In the Doctor Who episode "The End of the World", Mercury, Venus and the Earth are engulfed out by the expanding sun. Although Earth's technically an uninhabited protected landmark by that point.
 * In series 5's.

Tabletop Games

 * Normally, the card game Nuclear War only goes so far as allowing players to irradiate the planet in a Class 3a or Class 4 situation. However, the rules state that if a player launches a 100-megaton warhead and spins the (improbable) "Hit nuclear stockpile" result, the game instantly ends as a chain reaction engulfs the planet and the entire solar system in a nuclear fireball.
 * In the RPG Traveller, the Darrians have a weapon that can send a star nova.
 * Warhammer 40,000 naturally has one of these as well. If several Blackstone fortresses are linked, they can make a star go supernova and consequentially destroy the star saystem with it.
 * Also, the Necron C'tan used to eat stars. Before they decided sentient beings were tastier.

Video Games
"...vast spherical space stations that can drift from system to system with a forboding slowness, detonating stars like gaming's biggest exploding barrels. The resulting supernova annihilates every planet and ship in the solar system, leaving only a few asteroid belts composed of the detritus... I call mine the Starfucker Extreme."
 * Star Ruler allows the player to blow up stars, with sufficient firepower. The star will go nova, annihilating everything in the system - planets will be blasted apart, and any ship that can't outrun the explosion or jump away will be wiped away in a nuclear hellstorm.
 * Final Fantasy: Endless Nova revolves around this.
 * The plot of Star Trek: Bridge Commander started and revolved around sun-shattering kabooms.
 * Sierra's Space Quest series has the Star Crusher, a (suprisingly small) energy weapon capable of vaporizing planets and detonating stars, thus theoretically capable of wiping out whole solar systems in one shot. Fortunately, the mad scientist who created it was exiled before he could use it, and his research confiscated.
 * Of course, the people that confiscated the research didn't stop the project, oh no. They discovered their own star was dying, renamed the project the Star Generator, and used it in an attempt to save their planet. And apparently, no one expected the original mad scientist to get upset and try to take his weapon back...
 * In Space Empires, you can blow up a star, killing everything in the system. However, sometimes that's not enough - you can recreate stars and planets, after all. If that's the case, turn the system into a black hole, which also destroys the raw materials for planets. Then again, you can also destroy the resulting black hole...
 * Then put a new star back in place, and put a Dyson Sphere around it, making the materials for a massive sphere from virtually nothing...
 * Galactic Civilizations II includes, in one of the expansion packs, the Terror Star: a moon-sized space station:

"But there's a big difference between owning something that can destroy stars, and actually destroying one. The best weapon, after all, is one you only have to fire once. That's how Tony Stark did it, that's how his father did it, and that's how the Spatial Hares will do it. Unfortunately, I don't think the AI pays any attention to what happens to uninhabited worlds, so nuking Bikini Atoll wasn't going to cut it. In order to ensure I'd never need to use the Starfucker Extreme on a real planet, I had to use it on a real planet."

"Of course, I already knew a way to do that - I told you all about it on Day 6. The two ghost worlds I accidentally created, by colonising them with empty colony ships. I could do the same again here, and end up with an almost entirely empty world that still counts as an owned planet. It would be my almost-entirely-empty-world, of course, so I'd have to give it to the Terrans first - perhaps for a tidy price - then immediately destroy it to terrify them."

"And to think, they called me crazy. Tom Francis"


 * Free Space 2 ends in the Shivans doing this to Capella... for reasons that have not been explained.
 * In StarCraft II, a planet containing one of the Xel'Naga artifacts is being burned up from an expanding sun by the time Raynor's Raiders reaches it. Within a few hours, the sun will have engulfed it.
 * The backstory of the Halo universe states that the Foreruners deliberately did this several times in (failed) attempts to stop the spread of the Flood.
 * X Com Interceptor has the ultimate weapon as the Nova Bomb. When fired at a star, it takes about a minute to accelerate to light speed, at which point it is unstoppable. When it hits the sun, it instantly goes supernova, wiping out the entire solar system. You're supposed to use it to take out the alien superweapon, but there's very little preventing you from targeting a star the aliens have built several mining bases around and pulling the trigger. The star does in fact disappear from the map.
 * Mass Effect brings us an example in the second game's DLC Arrival.
 * Zone of the Enders: The Second Runner features the military fortress Aumaan, which when activated, can radiate enough energy to swallow the entire solar system.
 * The Pfhor, the Galactic slaver empire in the Marathon Trilogy, have a Trih Xeem in their arsenal, a Jjaro technology which roughly translates to "Early Nova". Guess what it does. They deploy it when they take heavy casualties or lose outright when waging Wars and/or suppressing slave revolts.
 * The Pfhor, the Galactic slaver empire in the Marathon Trilogy, have a Trih Xeem in their arsenal, a Jjaro technology which roughly translates to "Early Nova". Guess what it does. They deploy it when they take heavy casualties or lose outright when waging Wars and/or suppressing slave revolts.

Web Comics

 * In Schlock Mercenary, various races and governments have blown up a Dyson sphere with obscene quantities of more conventional firepower.

Western Animation

 * Unicron, while mostly known for eating planets, has also eaten stars, albeit never on screen. It's All There in the Manual.

Real Life

 * We have 5 billion years until it happens naturally in our little corner of the galaxy.
 * While our sun's red giant phase will destroy the inner planets by swallowing them, those planets that won't be swallowed (which includes all the gas giants) will survive quite well so this won't be quite an X-2. Plus the sun will still be there as a white dwarf.
 * However, in the very far future (many billions after many billions of years) the probabilities of a star passing so close to our Sun that planetary orbits will get disrupted increase. It has been estimated that after a quadrillion (1.000.000.000.000.000) years our dead and dark Sun will have all of its planets stripped, so by then the Solar System will have ceased to exist.
 * And, of course, there are various natural processes that might culminate in Class X-2s, such as supernovas and Gamma-Ray Bursters.