Did you like Sunless Sea? You’ll like the Zubmariner expansion. Did you dislike Sunless Sea? You’ll dislike the Zubmariner expansion. You will like or dislike Zubmariner in exact proportion to how much you liked or disliked Sunless Sea. Got that? Fab! I’ve saved us both ten minutes. Still not sure?

Here it is in logical notation:

You like Sunless Sea ⇔ You will like the Zubmariner expansion

I can draw it as a graph:


I really like Sunless Sea, so I really like Zubmariner. Zubmariner releasing is great news for me because I wasn’t reviewing games back in February 2015 when the base game launched. Now I can rave about it and look like a professional reviews person, not just a foaming fanboy who inexplicably has contributor access to a gamer website. Here’s the goods:

“You like Sunless Sea ⇔ You will like the Zubmariner expansion”

Sunless Sea is a text adventure dressed in top-down, boat-piloting, roguelike rags, in a world where London was stolen by bats and now lies on the edge of a vast subterranean ocean called the Unterzea. You create a Zea Captain, picking their history, ambition, and title – typically I am ‘Lady’ or ‘Comrade’ – and then fling them out to near-certain death in a leaky tub with rubbish guns and an unsavory chef. Gradually you’ll discover the ocean’s islands – their positions are shuffled up for each new captain – and the weird or sinister goings on at each of them: memory eating bees, indigent tiger people, unspeakable banquets, colonies of postmen. These encounters unfold through a choose-your-own-adventure text interface. Some choices will test your stats while others require a grab-bag of items from the game’s catalogue of fabulously titled oddities: you might swap drowning-pearls for solace-fruit at a pirate haven, or sell a searing enigma to an Alarming Scholar in hopes of buying a Cotterell & Hathersage Pneumatic Dynamite Torpedo Gun. Upgrade your boat, hire on dubious new crew, and you might just survive long enough to raise an heir and bequeath them your waterside house and collection of knicknacks. Actually completing your goals is easily forgotten when it’s so much fun to just bathe in the rich absurdity of it all.

Zubmariner adds underwater exploration, locked behind a modest quest chain that you need complete only once. Beneath the waves are fantastical settlements shrouded in yet more mysteries. They’re as inventive as the base game’s islands, and feel like the world of Sunless Sea extrapolated beneath the waves; whimsical, evocative, and shot through with ink-dark humor and references to Victorian political philosophy. They’re also an opportunity to delve just a little deeper into the world’s lore, and this stuff is juicy. Neil Gaiman, China Mieville and Catherine Valente are your literary reference points. Undersea settlements play out just like the base game’s islands: witty text adventures, albeit a tad damper than before.


Looked at this way, Zubmariner is just more Sunless Sea. That’s fabulous news if you’re already a fan and why, if the base game left you cold, the expansion won’t change your opinion. And there are plenty of valid reasons to dislike it.

The choose-your-own-adventure islands I’ve been talking up are like delicious croutons in a rather bland, boat-piloting soup. You control your boat from a bat’s-eye perspective, managing supplies of fuel and food, and hoping that your hull and sanity are not eroded by marauding pirates or unspeakable horrors of the deep. If that sounds cool, sorry — dial back your expectations. The ocean is mostly just a lot of old water. Unless you were really into the long, slow, planet-to-planet navigation in trading games like Elite – the part of the game when nothing happens – this probably isn’t your bag. It’s all just a bit too slow, and once you know the layout of the Unterzee it’s repetitive too as you shuttle back and forth between islands chasing out the last few stages of a quest chain. I have several friends who were captivated by Sunless Sea’s storytelling, only to have their enthusiasm crushed by the banality of actually getting to the story.

“Zubmariner is whimsical, evocative, and shot through with ink-dark humor and references to Victorian political philosophy.”

Zubmariner mitigates this slightly. Once you’ve unlocked the capacity for zubmarine travel you can dive under the waves and avoid any surface routes you’ve exhausted. In the almost-total-dark your zonar marks objects of interest with a shimmering aura; turn your hull lantern on them and you could reveal the carcass of a great sea beast, a treasure-laden wreck, or the bio-luminescence of an undersea predator. While the base game had random encounters at sea these are far more common and being able to opt into them makes traversal feel more interactive. Other small flips to the gameplay, such as underwater currents to exploit or hull-degrading weeds you must avoid, make zubmarine exploration a more engaging prospect than surface travel. Marginally.


At least it looks the part. In the limiting graphical framework imposed by the 2D overhead perspective Failbetter have done well creating the oppressive murk of the ocean abyss. Particle layers, subtle animation, and clever lighting create a motive seascape that bobs with half-glimpsed debris and swaying weeds, and it’s oh so dark down there. The comforting thrum of the ship’s engine is filtered through water and steel, adding to the claustrophobic closeness. The illustration of the undersea cities is beautiful, a real treat for you cartographic fetishists, with the bonus that the bottom of an ocean in a cavern halfway to hell is a good excuse for the design team to bring out the really weird stuff. This stuff is great, but again — no spoilers. You’ll have to see for yourself.

I have to mention a few technical problems that might be a result of under-cooked review code but were still an arse. One quest I completed failed to register, and in another settlement dialogue options for a quest I shouldn’t have been able to access were available from my first visit. I had one hard crash when a text box failed to load. All easily patched, and Failbetter seem pretty good at post-release support, but a bit of a shame.

Normally I would conclude with a pithy final analysis, but I think the first paragraph about covers it. You already know if you want this, and if you’re unsure, refer back to the graph.