Warning! Spoilers ahead for Darth Vader #11
In the latest issue of Marvel Comics' Darth Vader, the Dark Lord of the Sith finally tries to kill his master, but his attempt proves too pathetic and laughable for Emperor Palpatine. After being left for dead on Mustafar with his failure to capture or kill his son Luke during The Empire Strikes Back, Vader learned much on his journey to survive and get revenge against his master. Now, Vader actually tried to strike fear in Palpatine and kill him on Exegol in this new issue. However, the Emperor proved that his own powers in the dark side of the Force were far greater than that of his apprentice.
In previous issues of Darth Vader from writer Greg Pak and artist Raffaele Ienco, Vader clawed his way towards survival on Mustafar, using discarded battle droids limbs to replace the prosthetic ones his master had taken from him as part of his punishment. Furthermore, Vader proved himself to be quite capable without his lightsaber or powers in the Force, despite being hunted by the Sith assassin Ochi of Bestoon and a band of pirates. The dark lord also came face to face with the Eye of Webbish Bog, who granted Vader a Sith Wayfinder. This of course led Vader to the Emperor's secret Sith world of Exegol, and he even bent a massive summa-verminoth to his will. As such, Vader believed he had enough power, rage, and hate to finally end his master once and for all...he was incredibly wrong.
Darth Vader #11 sees the Emperor already waiting for his wayward apprentice, and he seems barely concerned by the summa-verminoth Vader has dominated. As the Emperor quickly proves, he's always prepared for everything, summoning two massive creatures of his own to attack Vader and his beast. Despite the creatures being killed by Vader and his monster, Palpatine simply killed the summa-verminoth himself with the Force, completely obliterating any leverage or power Vader thought he had against his master, and the Emperor found his apprentice's attempt to kill him laughable.
In just a few short moments, Vader was put back in his place by his master. However, Vader was still galvanized to kill Palpatine and he followed his master, venturing into the same Sith temple his grandson Kylo Ren would enter years later in Star Wars: The Rise of Skywalker. While the Emperor displayed his physical power outside, Vader then got a taste of his total power and influence, seeing the clones he had created, the legions of followers at his command, and the immeasurable fleet being constructed with planet-killing capabilities.
As a result, Vader severely underestimated the position he was in, and the Emperor makes sure that he knows that the true and unlimited power Vader craves has always been outside of his reach, being held by Palpatine himself. As such, the issue ends with Vader seemingly rejoining the fold, his pathetic failure of an attack serving to remind him of his lesser power when compared to that of his master. It also makes Vader initially telling his son Luke that it was too late for him to be redeemed much more significant in Return of the Jedi. After all that he's seen in this issue, Darth Vader must have felt that there was no way out, seeing no avenue to ever defeat his master.