Horizon is one of the best games I've played. It's a unique story with amazing mechanics for the limitations of PS4 controllers. I'll be honest, I do not particularly like using a controller on a third person shooter. With a – 5.00 in both eyes, I'm not what you call a "solid shot". This didn't seem to matter too much in Zero Dawn. Headshots were difficult a few times, but totally manageable. It felt challenging but not because of the mechanics, which games so often are.
Yet, the mechanics of the game do so much more than allow me to take down enemies easily. They also feed into the story. Throughout the story, from the very beginning, you control Aloy alone. Even as a little girl, you feel her solitude when it throws you into a cave with her. Aloy is alone. She is shunned. There's no child willing to take this trip with her. There's no companion.
Later, when you meet Rost, you're comforted by his presence. He walks with you, guides you through the tutorial. You feel a kinship with him. You feel his fatherly affection in how he protects you and makes sure you don't get too far into anything before you are ready. He prepares you for the world in actual videogame actions as opposed to cutscenes. He is the only person who matters to you.
And then he's gone.
After that, we experience Aloy alone. She walks alone. Fights alone. We feel her seclusion in a way that's very personal. Many times as I was wandering, I thought back to my experiences with Dragon Age or Skyrim and longed for a companion to join me. I found myself excited when I met Nil, and saddened when we departed from each other over and over again. Sylens brief conversations with me took away the loneliness, but they left as soon as they came. Again, I, Aloy, was alone.
And it's not as though people didn't want to try to join me. Many asked to come with, but each time Aloy rebuffed them. Many asked for me to stay, but again, Aloy said no. I felt frustrated sometimes by this isolation and I couldn't figure out why it unnerved me so much.
It's depression. Clear as day, Aloy suffers from depression. She wants to belong somewhere, but she never lets herself put down roots. She purposefully pushes people away. We see that she cares for them, she definitely does, but she is unable to form a connection to them. Her smiles are half hearted. Her celebrations are minimal. Even as the world cheers, she keeps going. She has to distract herself. Survival means she can't internalize.
It's done so subtley, you wouldn't even notice it unless you felt it. Horizon shows us that even the main hero can feel the overwhelming isolation that happens with depression. How it changes your relationships. How it ends up defining you if untreated or unnoticed. It doesn't mean she's crazy or damaged or weak. Depression is a hell of a beast, and not even the special redheaded protagonist is exempt from its hold.