Warning! Spoilers ahead for Berserk chapter 331!
Guts might have suffered the horrific Eclipse when he first meets the annoying elf named Puck, but his treatment of the elf in Berserk is heartbreaking when taking into account a flashback that happens much later in the manga.
Guts first meets Puck in the debut chapter of the critically acclaimed series by the late mangaka Kentaro Miura when Guts inadvertently saves the imprisoned elf by slaughtering a band of bandits. Although Guts ignores the creature and eventually flicks him away due to his incessant talking, the true heartbreaking moment transpires when Guts gets captured and thrown into prison. Despite being flicked, Puck visits the incarcerated Guts to heal his wounds. Again, Guts ignores the chattering elf even after getting healed and actually goes so far as to say something hurtful when Puck asks why Guts saved him: "Idiot! Who do you think you are?! Why would anyone save you!? To think I'd risk my life for a little bug!"
While cruel on its own, a flashback in chapter 329 puts Guts' cruelty into perspective. The moment transpires before the Golden Age during Guts' days as a lone mercenary. Like in the debut chapter, Guts is captured and thrown into a cell where he suffers from high fevers, all of which are exacerbated by snow that blows in through the barred window of his prison. Guts would have died had he not been healed by an elf named Chitch who is bound to a lone flower growing from the stone floor. Guts soon forms a relationship with the tiny Chitch and promises to take her to a field of flowers that are the same as hers, much to the elf's joy. The story is bittersweet, especially as Chitch's flower is later destroyed (causing her to disappear). But Guts keeps the flower with him when he's released and almost dies in battle to protect it, all so he can follow through on his promise.
This flashback is upsetting because of how Guts later mistreats Puck. Not only is Puck an elf like Chitch, but he even uses the same powers to heal him. When Guts is awestruck by how Puck heals his wounds, readers assumed that his befuddlement was based on the elf's incredible powers. But now fans know it's because Guts is reminded by what Chitch did all of those years ago. And yet, Guts still ignores Puck and insults him. Puck eventually flies away in tears but returns when Guts escapes from prison and battles one of the series' terrifying Apostles. Guts doesn't apologize or even acknowledge Puck during this time, and in later chapters, he continues to call Puck a "bug" and greatly implies he doesn't want Puck following him.
It's understandable why Guts is so apathetic and even cruel in the early chapters of Berserk. He had recently witnessed his only friends getting devoured by terrifying monsters and his beloved Caska getting assaulted in the worst way imaginable - all because his former Griffith chose to betray them. This brutal act of treachery undoubtedly changes Guts for the worst, filling his heart with nothing but the need for revenge. Although understandable, this unsettling transformation from a victim into a twisted anti-hero is only worsened by how obviously desensitized he has become, especially when taking into account Guts' earlier dealings with Chitch. It's clear that the powerful memories from an earlier moment where Guts exhibited compassion in the most touching manner aren't strong enough to fill his tortured and twisted soul with kindness in the present day. All of this is even sadder when realizing that Guts was finally moving beyond his hatred for Griffith before the sudden and tragic death of Berserk's mangaka Kentaro Miura.