How many planet destroying weapons from movies and TV are there?
The Death Star is always the top of this list because not only can it do the job, but you actually get to see it destroy Alderaan. Just to be fair, Alderaan DID shoot first.
The Vorlon planet killer is the next up because they show it in action even if we don’t get to see it actually fire.
The Shadow Death Cloud also wrecks planets. But apparently it doesn’t destroy the planet. Just renders it uninhabitable. Hell, we’re doing that on our own without any fancy space tech. So it ranks below the Vorlons.
The doomsday machine in ST:TOS. You don’t see it actually destroy a world. But you get to see the aftermath.
The planet killing red stuff in the last ST movie was pretty cool.
Ming the Merciless had some kind of planet wrecker. You never saw it other than Ming flipping a switch. And all it did was some rather biblical earthquakes and meteors. So I guess it’s a runner up.
Same with the monoliths in 2010. Sure, they destroyed Jupiter. But the created a star out of it. So, not really a weapon.
There are literally dozens of doomsday devices from a single episode of your namesake TV show - the one where naked aliens come and steal everything and Bender time-travels using a tattoo on Fry’s butt.
Jack McDevitt’s “Academy Series” novels feature planet-killers (well, they kill all life); one of the many subplots involves discovering what they are and where they come from.
The Genesis Device – not intended as a planet destroying weapon, but works pretty well as one nonetheless.
Lexx
Vogon Constructor Fleets
Farscape’s wormhole technology
Galactus
Unicron
In addition to the Deathstar, the Star Wars universe has the Sun Crusher, the Darksaber, and World Devastators among a bunch of other super weapons. There was also the Yuuzhan Vong method of dropping a moon on its planet.
EE “Doc” Smith’s Lensman series had the following, off the top of my head:
Inertialess planets. You take a spare planet or two, install giant intertialess drives, and move them to just the right spot. You then turn off the drives, which instantly restores their previous velocity. If you’ve aimed them right, they smack into your target planet leaving a giant puddle of mush. To be safe, you pick two separate planets with exactly opposing intrinsic velocities, so that you can crush the target planet between them. This is in case the target planet has also installed intertialess drives, which would allow them to escape attack with just one planet. In a later book, they picked up the spare planets from an area of space where they had “normal” velocities of faster than the speed of light. Cause, you know, the earlier planets were too slow.
Negaspheres. These were basically planet-sized balls of antimatter, though he didn’t use that term. I don’t know if it had been invented when he was writing.
The “Sunbeam”. This was a beam weapon that, when turned on, collected the entire energy output of a local star and focused it into your standard ravening beam of unimaginable destruction.
Edmond Hamilton was nicknamed “World Wrecker” by his fans because of the many times he destroyed planets. I haven’t read him, so I don’t know of any examples. (Hamilton was married to screenwriter Leigh Brackett, who had script credits on both The Big Sleep and The Empire Strikes Back.)
I just remembered Mike Nelson destroyed a couple of planets on MST3K. One, he destroyed by asking the nanites to help him out. Another was destroyed by an unexpectedly powerful vinegar/baking soda bomb he made.
Rico mentions “Nova Bombs” and “Planet Busters” in Starship Troopers.
As the war between the Arachnids and Humanity grinds on, we humans develop an edge with planet-destroying missiles. Rather than wasting time and resources with a Mobile Infantry assault on a bug-held planet, Fleet just cracks it apart like an egg as they pass by.
By the time we’re ready to assault Klendathu a second time, however, this is not an option, as the Bugs have been sending POW’s back to their home planet. There’s a spirited discussion in chapter 12 about why it doesn’t matter if they enemy holds one prisoner or 1,000 - that any number of prisoners held by the enemy is a valid reason to start or resume a war with them.