Removed these from Star Wars because they're massively overlong walls of text, with 2,600 words between the three entries. If someone wants to sift through them and condense them into a readable length, be my guest:
Their battle happened simultaneously with Anakin (now officially Darth Vader) and Obi-Wan's who became evil counterparts as the only confirmed living students of their respective Force sides and former comrades. They had some similarities prior to the turn. In that both were, of course, brought-up in the Jedi Order. Each started off with an initial tutor as children (Yoda as Obi-Wan's and Qui-Gon to Anakin's) but would eventually be passed on to another master for a longer term to complete their training. (Qui-Gon as Obi-Wan's and Obi-Wan himself as Anakin's) Whilst each cared about their mentor, there was also some tension in their relationship due to holding key ideological differences. (In both cases it was due to Obi-Wan's more rigid by-the-book nature which clashed with Qui-Gon's willingness to defy the Jedi Council's authority and Anakin's problems with their restrictive ways) However they would serve as an effective team together and both characters would should they could humble themselves towards them in respect. (Before the Battle of Naboo Obi-Wan would tell Qui-Gon, "I'm...I'm sorry for my behavior, Master. It's not my place to disagree with you about the boy. And I am grateful you think I'm ready to take the trials." whilst later on Anakin would tell Obi-Wan as he's leaving for Utapau to find General Grievous, "Master, I've disappointed you. I haven't been very appreciative of your training. I've been arrogant, and I apologize. I've just been so frustrated with the council.") Both would also become prospective disciples to a Sith Lord (Obi-Wan to Dooku and Anakin to Palpatine) with them asserting that together they could bring justice to the Galaxy. However a big difference is shown when Obi-Wan resolutely refuses whilst Anakin ultimately finds himself seduced over to the Dark Side. They'd keep the positions as one of the last of their orders and the subordinate within it long into the era of the Empire. Each having a more "boots on the ground" type of role (Vader acted as an enforcer for the Empire whilst Obi-Wan watched over and protected Luke from danger on Tatooine) in comparison to their master who watched things from afar. (Palpatine from Coruscant and Yoda from Dagobah) Each would make the first attempt to turn Luke into a member of their order (Obi-Wan began training Luke as a Jedi after rescuing receiving Leia's message in R2-D2 whilst Vader made the first real push to turn him to the Dark Side by trying to goad him into anger for their duel at Cloud City) until their master had to come into the picture to finish the job because of his ally's inability to complete the task. (After Obi-Wan was slain in battle he would eventually tell him to go to Yoda for training whilst Luke wound up resisting Vader's efforts which led to the Emperor stepping in with his trap at Endor) Notably both would initially to spur Luke on with a mission to help people (Obi-Wan made his offer to Luke after they had watched Leia's distress message together and told him, "I need your help, Luke. She needs your help." whilst Vader would lure him to his trap at Cloud City by capturing his friends and inducing visions of them in pain for him to sense) and use the knowledge they have about his father as a means to sway him. (Obi-Wan's knowledge of him being a Jedi hero and Vader's concerning how he himself is actually Luke's father) Each wound up killed aboard a Death Star (Obi-Wan on the first and Vader on the second) by a Sith Lord (Obi-Wan by Vader and Anakin by Sidious) in Luke's presence. Notably on the part of each of them however they knowingly faced death with dignity in a willing self-sacrifice. (When Obi-Wan saw Luke had stopped to watch their duel he lets Vader cut him down whilst later on Vader himself would intervene to save his son's life from Palpatine no matter the cost knowing full well of his power) Both going on to become one with the Force and reunite as ghosts in the end.
Another interesting comparison is between Palpatine and Obi-Wan. Starting in how after Anakin loses his ideal mentor/father figure in Qui-Gon Jinn both men entered his life attempting to take on that role. But whilst Obi-Wan was more hard on him though had his best interests at heart, Palpatine showered him with all the praise he wanted to hear but really saw him as a tool that he ultimately found disposable. Anakin did wind up joining with Palpatine as a Sith Lord, but he wound up paying the ultimate price because of it. Both later on would also, alongside Darth Vader, vie for Luke's allegiance. Both of them wanting him to destroy his father, as Obi-Wan lost faith in his ability to return to the light whilst Palpatine wanted to replace him with a younger and more powerful new apprentice. Luke ironically enough coming to be led to believe that he must do so in order to become a full-fledged Jedi or Sith. With his defining moment coming when he defied both by sparing him. Using his compassion/attachment rather than burying his feelings or giving into hate as the two parties tried convincing him of respectively. Obi-Wan though is ultimately happy to see what comes of it and to be reunited with his redeemed old friend, whilst Palpatine becomes enraged and thus starts viciously torturing Luke which winds up giving Anakin time to decide to relent from the dark path and sacrifice himself to destroy him. Also notable is how each is shown advocating to their students, or potential students, to use their feelings in action. Both show it when counseling Luke to do so (When mentoring Luke Obi-Wan would advise him during an exercise to, "let go of your conscious self and act on instinct." and to "Stretch out with your feelings." whilst trying to turn him during his duel with Vader Palpatine would tell him to, "Use your aggressive feelings, boy. Let the hate flow through you.") whilst Palpatine also similar sentiments with Anakin earlier on. And another interesting angle to look at is comparing Palpatine and his relationship with Anakin in the Prequel Trilogy to Obi-Wan and his relationship with Luke in the Original Trilogy. Both at those times are one of the last members of an order of Force users thought to be extinct that are in hiding and awaiting the chance for a comeback. (Palpatine among the Sith and Obi-Wan among the Jedi) A humanoid alien (Darth Maul and Yoda) kept even more deeply hidden (Maul served as an assassin who operated in the shadows whilst Yoda watched things from afar on an uninhabited planet before becoming a teacher again) started as the only seen ally from their order at the time before managing to attain their second apprentice (Dooku as Palpatine's and Luke as Obi-Wan's) who played a more open role in the galactic conflict within the ranks of a rebellious organization (Dooku was the head of state for the Confederacy of Independent Systems and Luke served as an officer within the Rebel Alliance) and the eventual turn of Anakin Skywalker to their side. Interestingly, each's first pupil was taken from them because of their opposing counterpart. (Palpatine's first being Maul before he was lost in battle with Obi-Wan whilst Obi-Wan lost his own first Anakin to Palpatine after he achieved Knighthood when he was successfully seduced to the Dark Side of the Force) Both were stationed closely to and insert themselves into the lives of the current new up-and-coming Skywalker from a very young age (Palpatine watching over Anakin on Coruscant while serving as supreme chancellor after he joins the Jedi Order as a child and Obi-Wan takes up a life as a hermit on Tatooine close to Luke after leaving him there with his moisture farmer relatives as a baby to be hidden him from the Empire) who they hoped to have help them overthrow/destroy their opponents. (Palpatine getting Anakin to join the Sith and help spearhead the Great Jedi Purge whilst Obi-Wan hopes to train Luke as a Jedi so that he can defeat both Vader and the Emperor) Both presented themselves as a more understanding and supportive paternal figure/mentor who seeks to help them achieve their true potential in comparison to their official surrogate father who had been raising them that they had some frustration in as they feel they are holding them back. (Anakin's Jedi master Obi-Wan himself and Luke's uncle Owen) Both claiming that they are lifting the fog of lies that those who brought them up had surrounded them with. (Palpatine tries to have Anakin see the narrow-minded view of the Jedi Order and how they are not all that different from the Sith whilst Obi-Wan presents Luke with the real story of his father that his uncle lied about) Both attempting to broaden their minds from the worldviews instilled in them by those guardians. (Palpatine was attempting to open up Anakin to a larger view of the Force including the nature of the Dark Side whilst Obi-Wan introduced Luke to the very concept of the Force and its properties) Whilst arguably rarely outright lying to them, both played around with the truth in order to try and make sure they are steered in their intended direction. When questioned by the Skywalker on certain shady points, they both defended themselves by invoking the idea of how much is defined by one's own certain "point of view". (Palpatine brought it up to Anakin when debating about the natures of the Jedi and the Sith that he thought were not so different from each other whilst Obi-Wan would use it against Luke to justify how he delivered the story of his father saying, "Luke, you're going to find that many of the truths we cling to depend greatly on our own point of view.") Both however aren't completely honest with him. (Palpatine leads Anakin to believe that they'll find the way to save Padme with the Dark Side together whilst Obi-Wan isn't forthcoming about how Darth Vader himself is the man who was once Anakin Skywalker) If one wants to take it even further both wound up being killed by Vader, who as brought up before served as each character's apprentice for some time, aboard a Death Star in front of Luke. (Obi-Wan on the first when he allowed Vader to finish him when he saw Luke was watching and Palpatine on the second when he decided to save his son from him) Whilst Obi-Wan fully accepted his inevitable death with dignity, having learned from Qui-Gon how to become a Force Ghost, Palpatine screamed all the way down the chasm to his death in fear after a life of having wanted to cheat it.
There is an interesting comparison to be made with Palpatine's role in the Prequel Trilogy to Luke's role in the Original Trilogy in the grand scheme of the galactic conflict as well as Anakin Skywalker's personal one. As each is the titular Phantom Menace and New Hope that would be instrumental in bringing about the also titular Revenge of the Sith and Return of the Jedi respectively. Each was the new player that came onto the scene that'd disrupt the Galaxy's status quo. Both bringing the order of Force users they joined that was in hiding for a long time out of the shadows respectively. And both were also the ones to influence Anakin's major changes in allegiance. Both also cycle around between partners within their order through out the course of the films, whether it be apprentices in Palpatine's case or masters in Luke's. Each in the first installments starts with one (Darth Maul as Palpatine's first student and Obi-Wan Kenobi as Luke's first teacher) who gets lost to a lightsaber duel by the end of that chapter via being sliced through with a lightsaber by an apprentice from the opposing order. (Maul by Obi-Wan during the Battle of Naboo and Obi-Wan himself by Vader aboard the Death Star) Both by the second have another (Count Dooku as Palpatine's second disciple and Yoda as Luke's second instructor) who would wind up dying in the earlier part of the third film in their one major scene of the film. (Dooku was executed by Anakin during the Battle of Coruscant with some coaxing from Palpatine whilst Yoda would die of old age in his hut on Dagobah with Luke at his bedside) After that each would be the last of their order left and set their sights on converting Anakin to their side. Both would eventually turn themselves over to him and make their initial offers. (Palpatine revealed to him the truth that he was the Sith Lord in his office when Anakin came to report that Obi-Wan had engaged General Grievous and Luke surrendered himself to the Imperials on Endor at their Shield Facility with the aim of getting to talk with his father) However he stuck to his guns and handed them to his superiors. (Anakin reported what he had learned to Master Windu who would then go to apprehend him and later on brought Luke to the Emperor aboard the Death Star II) An intense lighstaber battle would break out (Palpatine fighting Mace's team of Jedi that showed up to arrest him and Luke's duel with Vader before Palpatine) and would end with the Sith on his back with the now enraged Jedi having to decide whether or not to kill him. (Windu above Palpatine as Anakin watches and later on Luke above Vader as Palpatine watches) Things work out to Anakin's current superior having the character he's conflicted over pinned down and being electrocuted as he's pleading for his help as he watches. (Windu reflecting Palpatine's Force Lighting back at him when he's got him down after their clash of blades and later Palpatine himself directly attacking Luke with it after declaring his refusal to turn) Both cases resulting in Anakin declaring, "No" and coming to his aid. Causing the death of his superior in the process, both times dealt with being cast down into a great plummet. (Anakin disarmed Windu which allowed Palpatine the opportunity to electrocute and throw him out his office window whilst Vader would later on throw Palpatine himself down a reactor shaft) His actions in those places signifying his change from Jedi to Sith and then back around to being Jedi once more. In each case it would lead to Anakin being physically maimed by a one-time mentor (Obi-Wan severing his remaining limbs at the end of their lightsaber duel and Palpatine's Force lightning fatally damaging him whilst being carried away) which resulted in his body being burned (The Mustafar lava flow setting him on fire and later the funeral pyre his son gives him) and his rebirth in a new form. (First as a cyborg who was more machine than man and later as a ghost who truly had become one with the Force) Also notable is how Palpatine is an expert chess master as consistently displayed throughout the saga whether it be his machinations that helped him become Emperor or his trap for the Rebel Alliance which is something that Luke starts to show potential for himself. Namely with his plan to free Han and defeat Jabba that counted on the Hutt to bring himself out into a more vulnerable position as well as placing his allies in key positions against him. Each trilogy ended with these characters in question having risen to dominance in the conflict. (Palpatine going from a Sith Lord in hiding and senator from a smalltime planet to reigning Galactic Emperor whilst Luke went from a farmhand on a backwater world to a full-fledged Jedi Knight and successful war hero)
Removed these from Star Wars because they're massively overlong walls of text, with 2,600 words between the three entries. If someone wants to sift through them and condense them into a readable length, be my guest: