Game Stories: Sunless Sea and the Rhythm of Tension

Sunless Sea is quite a novel game. Sold with the tagline of "Lose your mind. Eat your crew.", it's a game where you explore a tranquil gothic ocean dotted with wonderfully weird islands. You need to ensure that your ship has enough fuel to sail successfully, that your crew has enough supplies so that they don't start starving, and that everyone stays calm and doesn't start freaking out because you've been zailing for days and days in the middle of the dark waters that lap at your boat again and again with a practiced dripping glassy precision...

Well. That's Sunless Sea, and it's a game that does a spectacular job of illustrating a particular sort of tension in its gaming narrative: the tension of survival.

In Sunless Sea, you start the game with a home base in London, a great port where you have (relatively) cheap access to resources. It's also home to the Admiralty, which pays you money and fuel for coming back to London with reports on what's going on at different islands. There's a lot of places in the dark Unterzee, but you'll always wind up coming back home to London, because that's where most of the payoff lies.

Thin and Stretched
The core tension in Sunless Sea is something that I call "rubber-band tension". Every time I play, I feel the same basic rhythm: I strike out into the dark, keeping an eye on my resources, circling around the map, asking myself "if I push just a little further out, can I get back safe?" You stretch further out, knowing that if you go too far, you break your tether--you don't have enough supplies to get back to London. And when that happens, it's bad news. Game over! Then you start over with another captain and see how much you've learned.

Now, it's true that the more you play the game, the more efficient you get: you learn not to repeat rookie mistakes, and you can estimate your resources better. But that just means you can push further before having to consider whether you should turn back, and it tempts you to bigger risks. Because out in the darkness lie strange new places to discover, or perhaps islands where you can find the next step in the stories that you're unraveling. As you press out, you begin to dance along the end of your tether, and the most tense part is that you won't know for sure if you've gone too far until you try to return.

Beyond the Darkness
Sunless Sea uses a fog-of-war on its map, only it's an inky black fog of war. As you push out into the sea, you reveal bits of the map, dispelling the shadows that clouded it. Out there in the darkness are strange and rather cool discoveries. That's the reward for exploring and risking everything. The map shifts, however, and so you're never fully certain what lies behind a particular patch of darkness. This is the grist that begins to drive the mill.

It can provide a nice feedback loop as well: maybe you discover one island, then discover a second island, and you begin to feel like maybe it's okay to push just a little further, just risking a little more. This ties into a fairly common reward mechanism: people like to accomplish and find things, and so, perversely, exploring when you can't afford to explore winds up feeling very rewarding. Which, of course, is the point: that impulse to keep exploring gets pitted against your instinct to keep your ship surviving, which wants you to come back.

That's tension.

Two Opposing Forces
The most effective type of tension in a game sets two good things against one another. In Sunless Sea, it's the good of survival against the good of discovery. Both are priorities, but the importance of each one changes according to the game situation. When you're heavy on supplies, then discovery is more important. When you're running low, survival is more important. When you're somewhere in the middle, that's where the tension comes from: you don't quite know which one needs to be more important right that moment. If you're a risk-taker, you'll generally wind up being rewarded with more discovery, but you might pay for it.

Then again, sometimes you wind up in a situation so dire that you go full-bore for the maddest option available. Such as charging at the giant sentient killer mountain in your path. (No, really. It's in the game.)