Realistic underwater simulation is getting its first extension.Unknown Worlds’ early access make-Joe-wee-a-little-by-having-eels simulatorSubnautica received an update which massively builds on the base-building sections of the game as well as adding a new biome.gameplay:

The biggest changes are to the base flooding system – should your base take damage and be breached, water can flood in and eventually drown you. It’s always been a source of utter terror for me, but now the deeper you are and the smaller the base, the faster it will flood. To help combat that, hermetically sealed bulkhead doors will allow you to completely close off sections of the base until you’re able to fix them.Alongside that, new modules to expand underwater bases have been included. The one Unknown Worlds seems most excited about is the moon pool, which will let you park your submarines right inside the base. Power generators to help power the modules have also been added.It looks like one of the biggest updates Subnautica has had. The lack of real base-building up to now has been a constant problem for me, as it’s meant there is little reason to keep playing after a certain point. With this new expansion, I’m more likely to keep a save for more than 20 minutes, which is nice.Subnautica, to make use of someone else’s reductivity, is basically underwater Minecraft, but even though it’s still an Early Access game, Ian liked it quite a bit in his preview. And he (and we) will probably like it even more now that the Habitat update is out, because now players can actually build a base on the bottom of the sea, complete with large rooms, panoramic observatories, and even a moon pool.

A moon pool!

Alas, that isn’t quite as cool as I first thought it would be. As Wikipedia explains, moon pools are openings in the floors of marine vessels or underwater installations that provide access to the water in a calm and protected environment. In the case of Subnautica, the moon pool serves as a dry-dock for the Seamoth submersible—practical, but still something of a letdown.

The moon pool, glass-bubble observatories, and generic “large compartments” can be strung together with standard and glass corridors as well as vertical connectors, giving completed bases a look that falls somewhere between BioShock and Habitrail. Compartments have eight attachment points for connecting corridors, dive hatches, windows, and other base modules, and can also be customized (a little bit) with wall-mounted lockers, signs, and even an aquarium.The update also brings with it a new Biome at the 200-450 meter depth, which includes unidentified flora, resources, and danger. Details on all of it, plus a cool little interactive demonstration of how habitat flooding works, are on the Subnautica Habitat Update page.