The lower in the Tower he is forced to go the heavier and more suffocating the weight of the levels above him becomes, but the lack of light is a heavier weight in his mind than any amount of stone could ever be.
There is too little of it everywhere, but the solitary floor is the worst; no windows at all, not even high up, and the cells themselves so deep down in the dungeons that he can almost feel the lake that surrounds the island around him. He imagines the layers that trap him; stone, then earth, and water last, painting them in his mind’s eye to distract from the darkness, the first and most suffocating layer of them all. There is no time when wrapped in it, only the slight difference between waking and sleeping, the uncomfortable embrace of the Fade or hazy, muddled thoughts. He needs a distraction from the dark as well as the oppressive loneliness, but the images he calls to mind only add to the weight above him and around and inside, and then all he can do is wrap his arms around himself and try to escape to a place where he can think of nothing at all.
When they let him out again, what light there is hurts both for how unaccustomed his eyes are to it and how it is still too little, too dull. He recalls thinking of it as an eternal dusk when he was younger, eyes desperately searching for windows low enough to let him see sunlight and how he used to climb up to look out of them when he had the chance. Back when he had the energy for such adventures, before solitary and more seeped the fight from his body.
The closest he has to the sun he longs for but now lacks the strength to reach out to is the sun of the Chantry; its sun brands on Tranquil foreheads, Templar sunshields and the red banners emblazoned with the rays of the Andrastian sun. The Chantry being filled with them should make him feel at peace and fill his heart with joy over the reminder of being in the Maker’s light, but it does not, because he is not; cut off from the light of the Maker’s creation, how can he be in His light? The Chant itself speaks of there being no darkness in the Maker’s light, but darkness is a tight knot of constant despair in his chest during the day and a black city at the edge of the horizon in the Fade at night.