Depth of Extinction is a turn-based strategy game about assembling a squad of soldiers, cramming them all into a submarine, and exploring the water-logged ruins of a once-prosperous Earth. As solo developer Mike Stumhofer told me when I played it at a recent convention, it's a little bit XCOM and a little bit FTL, and if you're interested, you can technically play it right now by buying into its limited First Access run on Itch.io
The missions I played all had three-man parties, but you can command six or more soldiers at once judging from the screenshots on Steam. Likewise, while my time with Depth of Extinction was mainly spent completing standard missions—infiltrating an area, finding and looting the target, and making it back to the sub, guns blazing—Stumhofer says myriad mission types are planned for the final game, with a variety of objectives between them.
The influence of FTL is clearly visible in Depth of Extinction's permadeath, and also in the way it's structured. From a static starting point, you bounce between locations of your choice, picking up soldiers and resources as you go. Expanding your party is as important as upgrading it, in no small part because you never know when you'll lose a soldier in battle. You don't want to put all your eggs in one basket, so to speak. Luckily there are 11 different soldier classes, and you can deck them out in "more than 150 different weapons, armor and items."
While your party's submarine is primarily a means of transportation, there is some sub-on-sub combat. However, rather than naval or underwater battles, these play out as standard turn-based fights where your sub is the battleground. From what I've seen, sub battles generally offer less cover than most levels, which are peppered with low, middle and high-level cover, most of which is fully destructible.
Depth of Extinction is scheduled for release this summer.