If anyone is interested:

Web: https://andrettin.github.io
Trailer: https://www.youtube.com/watch?v=7fL-2gGMrUI
Data repository: https://github.com/andrettin/wyrmsun
Engine's repository: https://github.com/Andrettin/Wyrmgus
Windows releases: https://github.com/Andrettin/Wyrmsun/releases

Was looking really interesting up until "Get Wyrmsun for free on Steam!"

Your reaction sounds pretty irrational to me. It's free and open-source, right…

"Wyrmsun is open-source and freely available outside Steam. Its data repository can be found here, and its engine's repository is available here."

Next time, read everything ;)

i think nightcraw1er.488 is right. you can download a zip of the game from their site without steam, but there's no exe and it seems it's just some old version. 2.0 and newer versions are only available on steam as far as i can tell.

You don’t need to go through Steam, the full source is on GitHub:
Game data
Game engine

True, but not everyone is willing to compile it for themselves.
I think a ready-to-run version outside Steam would be in their best interest, as a convenience.

EDIT: thank you for the reference, nebulosas.

Update: added trailer and Windows releases for those who want to try it.

bump

The releases for the data repository always include the EXE file, see here:
https://github.com/Andrettin/Wyrmsun/releases

Great game! It looks like it has been build upon a Stratagus/Wargus engine. Thank you for providing links.

A very tiny bit reminiscent of the Warcraft games, though the videos are a couple years old. Maybe it's changed since then?

On the other hand, on their front page they credit some of the lore to another open source game named Battle for Wesnoth (and linked to it). I'd forgotten about that game, had tried it some years ago back when I was fiddling with FreeCiv. Its front page offers the game for all desktop platforms (and OpenPandora??), and source, and even mobile, and its multilingual. It even offers modding with its own Wesnoth Markup Language (WML), and Lua scripting, with reference links. Seems very developed, for over ten years it says. Looks a lot different than I (vaguely) remember it, maybe I'll try that again.

I first played it many years ago. After a couple of years I looked at it again and it had evolved a lot. It is probably the most polished Free game I know of. Great music and graphics and pleasant interface and gameplay.

A new stable version is expected to come out in April, so you may want to take that into consideration should you want to start one of the longer campaigns, as the savegames may not be compatible.

Well, various tiles are indeed from Warcraft 2.
Anyway, from the video the game looks nice.