Dungeon Crawl Stone Soup Love this traditional roguelike!

Beyond All Reason

https://www.beyondallreason.info/

It a grand scale RTS game with robots and insects loosely inspired by Total Annihilation.

Did you guys tried Endless sky? Awesome game if you love space

Thanks for the Veloren recommendation, I liked Cube World, it just didn't work out well.

Cataclysm DDA Is THE open world zombie survival experience. So long as you like obtuse roguelikes with nearly no graphics.

Although Im obviously biased what with being a dev and all.

Mindustry is a really fun automation/tower defense game

Battle for Wesnoth is a personal favorite of mine that I haven't seen mentioned elsewhere in the thread. It's a pixel art, hex-grid turn based strategy game with fantasy armies. It's mixed with mild RPG elements, and there's tons and tons of campaigns and fanmade content accessible directly through a mod browser in game.
The other games I enjoy that I see being mentioned here are in the same vein. BAR, Warzone 2100, OpenTTD. And the open mods based on the STALKER engine, like Anomaly. I love those.

Dungeon Crawl Stone Soup for me. A classic roguelike with active community and regular updates as well as several forks. It also has a good amount of playable races. From classics like elfs or orcs ~~and dwarves~~ (RIP Mountain Dwarves you were too good for this game) to funky races like Vine Stalkers (sentient parasitic plants) and Armataurs (centaurs but with armadillo parts instead the horse ones) to cats and octopuses.

And the gods you can worship in the game are also very diverse. How about a slime god? Or someone who wants you to wear as much cursed equipment as possible in exchange for knowledge? Or maybe the one who wants everything to move veeery slooow and rewards you for killing mobs that are faster than you?

OpenTTD is good

CataclysmDDA is an amazing open source roguelike. Has a bunch of tilesets if you don't like ASCII

I haven't seen any incremental games get posted. They aren't exactly traditional games, but so many of them are open source like Antimatter Dimensions or Synergism. Bitburner is a unique one as an incremental hacking sim, since it relies on actual scripting to grow and automate tasks.

I really enjoy Thrive, it's basically a modern and more scientifically accurate Spore!

Warzone 2100. It reminds me of the older Command & Conquer games with a ton of upgrades and customization for your units.

Classic roguelikes have the most longetivity for me. Crawl, Brogue, Nethack.

Shapez is a fairly relaxing factory game. Pretty minimalistic style but easy to lose tons of time to if you aren't careful.

Here's a good start.

Fillets-ng (sokoban puzzler)

Simon Tatham’s Portable Puzzle Collection (sgt-puzzles)

Sauerbraten (FPS)

0 A.D. (RTS)

Holotz Castle (platformer)

Xmoto (motorbike trials riding)

Kobodeluxe (shmup)

Neverputt (minigolf)

Cataclysm: Dark Days Ahead

Veloren

If you didn't already suggest it, I would have suggested Veloren!

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