Explore-o-survive 'em up Subnautica [official site] might not have yet left Early Access, but it has now entered my cool books. Docking ships in video games is pretty great in general, a small moment hinting at the grand scale of a world, and even better is docking inside a larger vessel you can also control. Subnautica has that now. An update yesterday added a big new multi-level submarine you can dock smaller subs with and clamber around inside of.
The fifty-metre Cyclops is intended to be a home away from home in the depths, a place to return to for crafting, to replenish your air, and to hide from terrible things. It's got room for a choice of expansion modules too, though Subnautica only has one anyway at this stage of development.
It's made to go comfortably to 200 metres, which seems awfully shallow for such a fancy-looking vessel but I suppose alien seas have their own hostile rules. Even at 100 metres, water pressure means idly knocking into things brings a real risk of hull breaches you'll need to run around fixing.
Subnautica will still be in Early Access for a fair while yet, but Marsh Davies had fun larking about in the shallows with his snorkels, flippers, and dread of what lurks in the deep. It costs £14.99 on Steam to get in, if you're curious. This latest addition does have me tempted.