When Cornelia Geppert, the creative director on Sea of Solitude, first sat down to design the game’s monsters, she focused on specific emotions. The game, which launched last month, is about a young girl named Kay facing her personal demons, which have turned into real monstrous creatures. Geppert says that, with a black pen in hand, she “imagined the pure feeling of desperation, anger, [and] confusion” she wanted the monsters to represent, but nothing much came out of the process. She ended up with a page full of black scratches.

Then Geppert tried a different tack: she started to think about how the creatures would relate to specific characters. One of the monsters is meant to represent Kay’s mother, for instance, who spent years trying to keep a small family together, often to her detriment. In the game, she appears as a huge octopus-like creature covered in black fur and tentacles — perfect for holding on to things. “Every design has such underlying meanings,” says Geppert.

The art style of Sea of Solitude plays a particularly important role in the game. It’s a story that deals with heavy topics like depression and mental health, but it also attempts to visualize those intangible concepts. Kay isn’t exploring the real world; instead, it’s a kind of dreamscape where she’s constantly confronted with issues from her past. The game takes place in a sunken, destroyed city based on Geppert’s hometown of Berlin. As you explore, you come across all kinds of creatures that are meant to represent various members of Kay’s family and other important people from her life.

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Geppert says that the look of Sea of Solitude was defined fairly early in development. The director has a background in creating art for comics, and she wanted a similarly flat look for the game but translated into a 3D world. One of the challenges, though, came with the colors and the contrast between light and dark. Not only is Sea of Solitude a dark game thematically, but it can also be visually dark as well. Often, Kay will find herself shrouded in shadows or subject to dark clouds blanketing the city with rain. Almost every character — Kay included — is rendered in an unnaturally pure shade of black with glowing red eyes.

But Sea of Solitude can also be bright and colorful at times. The sunken city features clear blue waters, lovely hazy sunsets, and crisp mountain snowscapes. Finding that balance between the two extremes was a big part of the development process. In fact, early versions of the game featured a much darker opening sequence, which was eventually changed to reach that equilibrium. “We started refining it to have a good balance between sunny weather and creepy weather,” says Geppert. “It was very important to us to give the player enough positive vibes in between to not drag them unintentionally down.”

That balance was particularly tricky when it came to the monsters. Initially, they’re incredibly scary, with towering forms that blend animals with humans. But they’re also meant to evoke real people from Kay’s life. Geppert says she wanted them to seem frightening at first, but to feel increasingly approachable the more you get to know them. In fact, she says that progression is ultimately the message of the entire game.

“People with mental health issues can seem overwhelming or intimidating at first when they open up to you, or just lash out unintentionally because of their suffering,” Geppert explains. “That means they first appear scary. That is what I wanted to represent with the scary monster designs. But in Sea of Solitude, same as in real life, when you approach them and interact with them, you soon realize that they are not scary at all but need support and understanding. They are no monsters at all.”

For more on the art and design of Sea of Solitude, check out the selection of concept art below.