system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars]What would have happened if the Death Star had survived the attack on Yavin?

Scenario 1: the rebel attack on Yavin fails.
Scenario 2: The Empire never finds the rebel base on Yavin, so they have the Death Star  but still have to hunt around.

How would the Empire do and how would they use the Death Star?
gpt
Okay so without specifics I'll try to suggest some likely answers to these scenarios. 

**Scenario One:** The TIE Fighter pilots observe Luke and his squadmates making a trench run towards the thermal exhaust port, and relay that information to Tarkin. Engineers aboard the Death Star inform him that an accurate Proton torpedo shot from an X-Wing would set off a chain reaction and annihilate the Death Star. 

Tarkin immediately commands his crew to jump to Lightspeed just to shake off these pilots, just as Luke has fired his torpedoes. The Death Star jolts to Lightspeed and causes the torpedoes to hit the inner sides of the exhaust port, instead causing a chain reaction of damage to other systems across the Death Star. Coupled with the Death Star also being within it's firing sequence (that it abruptly stopped), many of the systems (like Navigation) are damaged, and the main Superlaser cannot fire without risking destruction of the Death Star. Tarkin decides to beat a retreat with the Death Star, jumping to Lightspeed ASAP. The Death Star makes it as far as Alderaan before konking out, and Tarkin orders repairs to be done immediately. It won't be quick though as the damage is extensive, and a lot of the engineers have perished in the Rebel assault. 

Meanwhile the Rebels are simultaneously celebrating and arguing. They cannot decide as to whether they should celebrate forcing the Empire to retreat and use the period of relief to evacuate off-world, or instead they should make a follow-up assault on the Death Star while it's still crippled. Leia convinces the rest of the Rebel command that the threat isn't going to go away, and if anything if they give the Empire prep time they'll just repair the Death Star and fix any glaring weaknesses (like the exhaust port) now they know the Rebel's strategy. They immediately prep a new plan. Meanwhile Luke has had his first encounter with Force Ghost Obi-Wan, who begins training him in the Force (as he refuses to leave while the Rebellion is still in need of its best pilots). The new plan is revealed to be staging another assault on the Death Star, with the X-Wings piloted by astromech droids. Meanwhile two Rebels (an enthusiastically confident Luke and increasingly regretful Han) are to infiltrate a (relatively) nearby Empire encampment on Corellia, steal some Stormtrooper armor and two TIE Fighters (preferably without getting caught or by neutralising all present troops) before using them to infiltrate the Death Star hangar. 

The astromech squadron begins their assault as Luke and Han approach the Death Star. They manage to get inside without much issue due to the chaos erupting outside, they land and inform the inquisitive Imperial Captain that they have pertinent information for Tarkin regarding a Rebel attack on Corellia that relates to this assault. The Captain insists they make haste to Tarkin, so Luke and Han jog out of the hangar bay. They make it round to the Superlaser section of the station, and notice the machinery and circuitry is heavily guarded. Han of course is cynical and critical of this mission and its seeming impossibility at this point, whilst Luke tells him to pipe down while he begins to concentrate. He gets in the right frame of mind, tells Han to keep quiet, and they approach the (obvious by the authoritative position) leader of these Superlaser guards. Luke informs the leader that the generator is under attack by Rebels, and that they've already dispatched the rest of he and Han's team sent to crush them. Using the mind trick he tells the leader to take his team to go find and kill the Rebels before they blow up the base, and the Stormtroopers oblige. After they disappear from sight, Han gets to work rigging a "simple power cycling disruptor" (with Luke questioning his performance). The two out back the circuitry panel and make their way out, caught by the leader of the Stormtroopers who Luke mind tricked. 

The leader states that they found no Rebels onboard, and before Luke can attempt to mind trick the leader, Han interjects "Rebel Scum! They must have already made it into the exhaust port manifold! There's no time to waste!" as he and Luke jog past the speechless and confused Stormtrooper leader. They make it back to their TIE Fighters and leave, signalling to the Rebellion to send in their frigates. The naval might of the Empire arrives, firing upon the Death Star to little effect. Tarkin is getting antsy, and orders the Turbolaser crew (who reported the fully charged weapon as ready to fire) to fire upon the biggest command frigate. Unfortunately for the Empire, Han had reversed the energy flow from the Superlaser back into the Death Star's power generators, causing an overload of power that in turn would destroy the Death Star. The Death Star blows up, and the only Rebellion losses are all but one of the astromech squadron (of course being R2-D2), and the Rebellion immediately beats a retreat back to the Rebel base on Hoth (as the Empire would know about Yavin 4) before the Empire can track them there. The rest of the later plot happens pretty similarly to usual, except Luke is slightly better trained with the Force than usual, and Han is a less reluctant member of the Rebellion. 


**Scenario Two:** This is much less of a lengthy scenario. Leia knows the Millennium Falcon is being tracked, and so instead of landing on Yavin 4 they instead land on Yavin. Han carefully removes the tracking device, being careful not to deactivate it. They plant it in some nearby ruins, and quickly leave to rejoin the Rebels on Yavin 4. Taking a larger frigate ship loaded up with X-Wings and their pilots, a small cadre of Rebels pilot the frigate off of Yavin 4 and jump to Lightspeed to get out of the Yavin System. Han and Chewie leave the system also in the Millennium Falcon. 

The Death Star arrives in the Yavin System. They begin prepping to fire upon the "Rebel Base on Yavin", awaiting confirmation from Rebel scouts investigating the planet. They come under attack by Y-Wing bombers (sent from Yavin 4), which the Imperials take as meaning that the Rebellion *is* on Yavin (and that they're defending their base). The Death Star preps to fire, as the frigate reappears from Hyperspace. It deploys its X-Wings, and they enter attack formation on the Death Star trench. The Turbolasers fire upon the Rebellion frigate, and the Superlaser is fired at Yavin (hoping to disorient the attacking Rebels). Unfortunately for them, Yavin was the decoy base. Unable to recharge in time to destroy Yavin 4, Luke and his wingmen complete the trench run (with assistance from Han causing Vader to fly off into space). Events from here on go more or less the same, albeit with the Rebellion taking a more careful and intricate approach to all aspects of their operations in seeing how close they were to getting detected (by the ship possibly being tracked back to Yavin 4), and summarily blown up (as Yavin was).