Trainwreck

It bears reminder that the first four albums of Mastodon each represent an element. Remission represents fire, Leviathan represents water, Blood Mountain represents earth, and Crack The Skye represents Aether or Air. A lot of people already know this; but what many don't realize is that the progression from Fire to Aether actually represents the features of the earth from most inwards to most outwards. It begins in earths fiery core, then as you continue up you reach the water and the oceans, above the water you reach the land and earth, and above the earth is the air.

The mythological elements of Mastodon suggest that they are probably drawing correlation with the earths fiery core and hell itself. This would be in line with the flat earth religious ideas that hell is down and heaven is up.

Because Remission, the fire album, is probably associated with hell, we get lyrics that match it. Some of the most hopeless, tormented, and damned aspects of the human condition; As if they were roasting in hell. This album is defined by key traits of a fiery hell; Fury, Anger, Suffering, Hopelessness. Every trait associated with hell's circles.

This particular song is about life-breaking nostalgia. 'Trainwreck' is likely an allegory for the fixed, progressive (train) track of life, and how the train can be obliterated in a mangled catastrophic mess.

"life's changed yet remain the same"

This is a common sentiment of people that have a depressive nostalgic mental condition. The things and feelings that made their childhood and early years magical and vibrant just sort of disappear and things go dry. But there are also constants from that carry over from childhood that only serve to confuse and blur the victims perception. They can't decipher if they changed, if their surroundings changed, or if their very memories of the past are even real or just idealized.

"basking in an afterglow"

The character is fixated on the vibrance and color of the past. Nuanced kinds of perception and feelings that he lost.

"i did not know i am here in shadows island"

In his extremely cognitively dissonant introspection he's reconsidering the past and his memories. He didn't know that he's always been alone (island) and that life has been meaningless from the very beginning.

"lying hopeless wondering all questions exhaust me"

He's physically incapacitated by the circular thoughts in his mind as he introspects about the past. He's simply stuck lying there, thinking in hopeless circles that lead to no answers. It's a chemical-emotional and cognitive trainwreck. The questions exhaust him.

"running screaming chanting"

The thoughts are driving him completely insane. It's like a never-ending splinter in his mind, beneath his skull. This is basically a meltdown. Instead of lying down thinking in hopeless circles he goes berserk and tries to free himself of his chains physically.

"for all this land i've seen its worth"

One of the many ideas floating around in his cognitive dissonance-wracked brain takes precedence. He is struck by the conviction that his dark feelings about the present is all there is and ever will be. A similar sentiment is the primary theme of "March of The Fire Ants"

"helping all for times sake it brings me work"

In his depression and lack of meaning he tries to distract himself by finding a cause and helping others.

"pinned to this world"

This is prefaced by suicidal thoughts because of his condition. He is afflicted by suicidal thoughts but he knows he won't follow through with them, so he's pinned to the world and his soul can't break free. He's also probably burdened by the thought that there is no soul or afterlife to be had anyways, and the material that makes up his body, skeleton and being is just as pinned to his world as he is.