By the time Anakin Skywalker and Obi-Wan Kenobi meet again aboard the Death Star, it is clear that the both of them have changed greatly from the time they last saw one another at the Mustafarian Lava Lake. We guess taking a dip in lava following a great betrayal can do that to a person. Both have grown physically, mentally, and it shows when the former friends and now bitter enemies battle one another.
Though the original battle between the two from Star Wars: A New Hope was often derided for being boring, especially when compared to the lightsaber fights in the prequels and the new trilogy, it was still a great depiction of a fight featuring two battle-hardened men with too much history between the both of them.

Plus the original scene had a 60-year-old veteran actor going against a much younger stuntman in a mask and suit, we can see why the fight was a lot less dramatic than what we are used to.
That being said, YouTuber FXitinPost recently uploaded a short six minutes clip reimagining what the fight between Darth Vader and Obi-Wan Kenobi could have been. SC 38 Reimagined is a two and a half year pet project by FXitinPost which was first teased back in 2017 and is finally released on YouTube.

The video uses footages from the iconic scene in the original film, while adding in some new ones for the lightsaber fight sequences. Thanks to new technology and new fight choreography, the battle between Vader and Kenobi looks much more intense.
Even if you are not a fan of the franchise, you will still be able to appreciate the fight, watching Vader and Kenobi swing their lightsabers around and occasionally using the force to do battle. Though the video has some dramatic heft to it too, and fans of the series will surely recognise the final words the pair spoke to one another on Mustafar as Vader slices through the Kenobi’s robes, concluding their fight once and for all.