Full disclosure; I am close friends with the developer and did some beta testing of the game for them. I did, however, buy the game and will try to keep my review as unbiased as possible.

Exo-Leviathan is a short, fairly simple space-based horror game about collect dragon scales in an asteroid belt.

The rather simple premise (as far as I can tell) is that you're a Cadet working for an unnamed corporation that intends to study(?) the scales of dragons, and so are tasked with filling six carapace boxes. The story is pretty thin here, with the only dialogue being an opening text crawl that contains some world building, followed by objectives being fed to you through a pair of screens on your ship.
There is no voice work to speak of.

The general game play loop consists of collecting the carapaces, which occasionally gets broken up by a couple of other events that are tied to the narrative. While collecting carapaces, you'll also have to manage your oxygen levels when you're out on your space walks, and keep an eye out for a sort of 'dragon alarm' that will require you to power off your ship or become another victim. Ultimately ending in - for me - a satisfying way.

The carapace detector around your crosshair, which appears as arrows pointing you in the right direction, can be a little finnicky, especially on smaller asteroids, and can sometimes feel like trying to lead a cat on a leash. Thankfully, a beeping noise can also be heard to help you find them, which speeds up the closer you get to one.

There isn't much meat here. You do the objectives and finish the game. There are no collectables or much of a reason to explore the asteroid belt. There is, however, an alternate*ending!

It's simple. It's pretty. It sounds decent.
8/10, worth the reasonable price tag.