The project is far from complete, as over half of the sea's map is empty. There's another kind of emptiness in Sunless Sea, though, as even the accessible regions feel endlessly dark at times. This other emptiness, the pervasive, creeping fear of the unknown as you sail mysterious waters, is what makes Sunless Sea stand out, even at this early stage of development. In Sunless Sea, players commandeer a ship, traversing an alternate-reality, subterranean London surrounded by a dark and dangerous underground ocean, a locale created in one of the Failbetter's other games, Fallen London. This ocean, the Unterzee, is filled with opportunity, from the Admiralty officer that pays handsomely for visits to various ports, to the shadowy figure that offers gold via a middleman if you agree to smuggle goods. Towns like Venderbight house the mummified undead while Polythreme is home to the clay men.
Adventurous captains explore ports and talk with their inhabitants to build an understanding of the world and gain useful materials to sell and trade in London and other parts of the Unterzee, hoping either to build renown as a respected sailor or to retire in wealth and luxury. Each decision you make is rewarded with a card-like item, viewable in the inventory as a reminder of your encounters with other characters in the world. "Recent news" from London becomes a literal inventory item, which you might give to a patrol boat at sea in order to comfort its crew. A "tale of terror" told to you by a young maiden becomes a commodity, and the right person will pay for it.
Meanwhile, other items may lead you to unexpected places. For example, I discovered an odd piece of cargo at Venderbight with no destination label (just a note that it was meant for my ship) and delivered it to another port, unraveling a story about a strange scientist performing autopsies on a seemingly empty island. Some decisions have weighed on my mind, though nothing has come of them yet: After accepting money from the mystery man for my misdeeds, I chose to deny further interactions, which may or may not be to my benefit later on. Even as an Early Access game, the web of choices and their consequences feels well-spun.
Of course, sailing from port to port wouldn't be much fun without a helping of lethal sea creatures to encounter. Shortly after exiting the safe confines of London's port, crabs nearly the size of my ship darted toward me. Not long after I avoided them, new crabs with lantern-like antennae that were definitely larger than my boat also began tracking me down. Taking on these and other, more dangerous creatures leads to real-time, turn-based battles. You're given four slots in your combat queue to shed light on enemies with mirrors and flares, each maneuver taking a set number of seconds to perform. Once an enemy's luminance is high enough, the captain's cannons are open for business, though a strategic commander might spend more time on evading their attacker's pursuits to avoid opening themselves up for damage as well. It's enjoyable enough when fighting new enemies, but grows a little tiresome when battling the same creatures time and time again and having to wait 20 seconds for each battle to wrap up.
Light is a key component of the game overall. The perpetual midnight ocean is interrupted by small islands and lighted buoys, each a welcome opportunity to escape the darkness, as any moment outside a lighted environment is cause for your crew to slowly go mad, represented by the terror meter. The meter is an effective motivator, and any excuse to remove myself from danger was welcome. Once, I allowed the meter to fill completely and was met with mutiny. Given a fifty-fifty chance, I managed to quell the mutiny, but even victory had its consequences, killing half of my crew and leaving me less able to deal with future problems.
Perhaps the best demonstration of Sunless Sea's chilling, uncharted waters is the fact that it's still in a beta state. Daring to chart a course to the northeast corner of the map results in a notice that nothing lies in the blackness beyond, at which point I was happy to turn around and find comfort in familiar ports. Even though I've encountered placeholder monsters and sailed to unfinished islands – Failbetter Games' transparent development roadmap pegs Sunless Sea's world at 38 percent complete – what sea stories I did witness had me wrapped up in the game's world, drifting from coast to coast to learn more about the circumstances of its inhabitants. I know I'll set sail again to see what tentacled and toothed horrors await.
This review is based on a Steam Early Access download of Sunless Sea, purchased by the reviewer. Sunless Sea is available now via Steam Early Access for $18.99. Images: Failbetter Games. Joystiq does not provide star scores for early access games.