WARNING: The following article contains spoilers for Star Wars: Age of Resistance - Supreme Leader Snoke #1, by Tom Taylor and Leonard Kirk, on sale now.
The cave of Dagobah, introduced in Star Wars: The Empire Strikes Back, has long been associated with the Dark Side of the Force, primarily because we had only seen it through the eyes of Luke Skywalker. However, in Marvel's Star Wars: Age of Resistance - Supreme Leader Snoke #1, the role of the location is far more complex: Like Ahch-To’s sea-cave in The Last Jedi, it’s instead a place where the Force tests visitors with their biggest fears and challenges, which in Kylo Ren's case have nothing to do with the Dark Side.
Providing a stark contrast to Yoda's training of Luke, the issue depicts Snoke's tutelage of his young apprentice, beginning with the hurling Kylo from a cliff, striking him in the face with his obsidian ring, and then sending him into that familiar cave on Dagobah.
When Kylo walks into the gnarly undergrowth, he first sees his uncle Luke in full Jedi garb, who tells his nephew he doesn’t want to kill him. Angry at his uncle's perceived treason, Kylo charges and slays him. However, Snoke, and the cave itself, are not yet done. Confronting Luke was only a warm-up for the true test: facing his parents, Leia Organa and Han Solo, desperate to pull him back into the light.
The theme of balance is a powerful undercurrent in both the original trilogy and the prequels, but it's front and center in the sequels. Luke literally confronted his shadow in The Empire Strikes Back, in one of the scariest scenes in the franchise. Luke was facing the enemy who gave the order to burn his aunt and uncle, slew his mentor and now pursued his friends. Surely only an evil place would torture our hero, and that Yoda chastised him for failing only reinforced the negative message.
However, in Supreme Leader Snoke, Dagobah’s true purpose is revealed: By showing Kylo Ren his parents, the cave is drawing him into balance by forcing him to acknowledge the part of himself he wants to bury: his love for his family. Not because love is a bad emotion, but because it's pulling him in the opposite direction of Snoke’s promises, and both his parent’s love and Snoke’s plan hinged around “that mighty Skywalker blood."
From a purely psychological point of view, the healthy step for Kylo would be to embrace his parents and reintegrate the part he had tried to bury, within himself, becoming stronger in the process. However, in this issue, set during Kylo’s formative years with Snoke, he wasn’t yet ready to do that. Of course, that doesn’t mean he would be able, or willing, to kill his own parents, even with Snoke's encouragement.
Therefore, Kylo takes the third option and decides instead to destroy the Dagobah cave.
In Star Wars, trees are symbols of life and stand-ins for the Force itself. Look, for instance, at the Sacred Jedi Texts contained within a tree in Ahch-To, or at the Uneti trees that adorned the Jedi Temple on Coruscant. By ripping Dagobah’s tree-cave apart, Kylo metaphorically chooses to kill the Force rather than to kill his parents. Another way to read this scene is as a foreshadowing of the way in which he kills Snoke in The Last Jedi: The way he severs the roots of the tree is remarkably similar to his bisection of the Supreme Leader. It also clarifies his motivation in that him; he didn't kill Snoke because he was in a rush to take over the galaxy, but because he was trying to protect who he loved from being destroyed.
Kylo succeeds, very literally, in killing the past by destroying the site where Snoke planned to bring future apprentices. The cave-tree test was deeply flawed, even back when Yoda taught Luke, mostly because the masters themselves did not seem to understand how it worked. And just like Yoda and Luke in The Last Jedi felt the need to burn the sacred tree that contained the ancient Jedi texts, so does Kylo destroy this remnant of old times.
The destruction of the tree-cave has an additional meaning, as it allows the light into Dagobah, and it frees Kylo Ren. The deep cave acted like the mask he was so attached to, threatening to drown him in the shadows of the past instead of allowing him to focus on the now. With the tree gone, Kylo’s present becomes crystal clear: a gilded master too blinded by hubris to see his disciple’s true power, and, in a nice callback to Rey’s Ahch-To mirror cave, only his reflection in the dark water to show him who he really is, and what he’s capable of doing.