Warning: Spoilers for Berserk chapter 371After years of suffering throughout the course of the utter hopelessness that saturates Berserk, Guts seems to have finally broken down. While the Black Swordsman may appear indomitable on the surface, all the damage he's received over the years has finally shattered him.
Perhaps the biggest crack in Guts' emotional armor came when Griffith betrayed him and their comrades. Normally Guts responds to this kind of pain with unfiltered rage, a loss of control that inevitably leads to at least one person getting mauled. It's understandable why Guts succumbs to such violent reactions so frequently since he's endured quite a bit over the course of the manga. But there's never really been a moment where Guts seems to be so overwhelmed by helplessness that he's actually afflicted on a physical level.
But that changes in Berserk chapter 371 by the late Kentaro Miura's successors in Studio Gaga. Following Guts' failure to save Casca from Griffith, the hero is trapped by hopelessness and locks himself in a storage room so no one can bother him. There, Guts' facial and physical reactions clearly demonstrate that he's suffering, especially when he falls onto the ground in the fetal position. His companion Schierke is so concerned by what's going on behind closed doors that she uses astral projection to reach his subconscious. And there in the Astral World, readers are given a more foreboding image of Guts' plight. After witnessing all of his darkest memories, Schierke watches Guts descend into darkness as though he were drowning, all while existential thoughts - most likely Guts' - fill Schierke's mind.
Guts Has
This reaction is the natural progression of what plagued Guts in Berserk's previous chapters. At first, readers believed then that it was because Guts had failed to rescue Casca from Griffith. While that undoubtedly contributed to his mental decline, what he fixated on in chapter 370 was that, for the first time, a sword failed Guts in battle, changing what his blades once represented. He realized that, before he had anyone else in his life, the only thing he had and could depend on was his sword. And now that was gone. This is essentially akin to when Guts lost the only comrades he'd ever had during the Eclipse. These feelings from before have now clearly escalated as of chapter 371 as readers find him believing that everything he's accomplished has been for nothing. This is indicative in the images Schierke sees of the many horrors Guts has witnessed during his blood-drenched journey.
What's intriguing is that Guts' mental anguish shares some visual correlations to when his Berserker Armor takes over. This doesn't actually happen in this particular instance, but some readers might find possible meaning in Schierke's sudden exclamation during Guts' decline before she's cut short: "It can't be...Guts is..." Of course, Schierke could just be having difficulty with the fact that Guts could actually be experiencing a mental breakdown. That, or she could be realizing that he's actually undergoing something much more sinister - as some of the artistic renderings seem to suggest. Regardless, Guts has apparently completely lost it for the first time in Berserk. What an ironic twist it would be if Guts went catatonic after Casca just came back!
Berserk is available in English from Dark Horse.