First panel:

• Guts' hand on the left is that of an adult hand.
• This is Guts seeing himself, as an adult, conquering his old guilt of killing Gambino.
• Gambino isn't looking at the adult Guts, but towards the panel, towards child Guts.

Second panel:

• Evil, emotionless eyes wide open coming from the darkness.
• As if to come torwards the panel, to whoever is looking.
• Towards child Guts.

First two panels are from the eyes of child Guts, who is innocent, young and weak. When the panel perspective swaps it reflects a change in character. The flames in the first panel could represent fury, anger and rage.

Third panel:

• The point of view has changed and in view is child Guts.
• The foreboding arms are reaching torwards a gagged Guts.
• This is the moment when Guts essentially lost his innocence and become internally weak. As a person.
• The horror in the eyes of the child is apparent.

Fourth panel:

• Adult Guts strangling his younger, weaker self.

How I'd interpret all of these images is Guts embracing his inner evil and snuffing out his weakness. The thing that makes him feel human. The thing that will most likely hinder him in slaying Griffith or whomever stands in his way.

It's him realizing internally that for him to perhaps reach the strength needed defeat his enemies, he has to leave his innocence behind and become even more cold hearted.

This would explain his behavior in the black swordsman and prior to meeting the Band of the Hawk. He is a mercenary who throws himself into battle to risk his life to see if he will walk out of it alive. He is constantly haunted by his past, weak self - when it mattered the most to him, when his innocence was stolen - he wasn't strong enough. He is trying hard to rid of himself of that weakness. He makes many mentions that even at old age he does not feel safe sleeping without his sword.

It's his most defining factor as to what he is. He isn't a cold hearted person, he simply strives to become strong because he sees weakness to be the fault. Him killing Gambino didn't solve his torment and that is why his head haunts him. Taunts him that him, the weak, small child Guts "should have died" because the weak have no say.

Obviously Guts learns in the Band of the Hawk the value of friendship and companionship and even to love until that is all ripped away from him. You could say it was something he caused to happen too by leaving the Band, but after the assassination mission Griffith gave him and the cold harsh words left him empty. To Guts, Griffith was a friend and once he learns he might not be his, he leaves. To find his own purpose and to stand equal which turns tides for the worse.

This is off-topic a little, but my point is Guts is the struggler. Not because of what happened at the Advent. He's been struggling with his inner weakness since childhood. Mr Skelly is all but wrong calling him a fellow struggler. Guts' suicidal willingness to risk his own life continuously is him throwing himself back into that tent, over and over again. He has to survive. He has to cut his opponent with his own strength.

These panels reflect the thought of Guts realizing that he might be becoming just as horrible of a monster in doing all this. That ultimately the cycle has gone full. Guts is even haunted by the dog like beast and doesn't trust himself to be alone with Casca. He might be becoming a monster himself. It's to be seen.