Open source game based on Transportation Tycoon Deluxe.
I wish it had a modern GUI though. The old one is almost unusable even though they've made an attempt to implement DPI scaling.
Mindustry is neat if you like tower defenses and factory/automation games.
[edit] Though this isn't exactly a game, I thought I'd mention it: The Powder Toy. Really fun physics-ish sandbox game if you like just playing around with little particles or making electronics or nuclear powered fireworks shows, etc.
Mindustry is great! I've put a ton of hours into it and I've gotten my kids into it. Super active dev and good community.
I prefer it to factorio
This was the first thing I thought of when I saw the title of the post. Mindustry is awesome, I got so addicted to it for a bit haha
Not a very original answer, but I still enjoy The Battle for Wesnoth after many years.
I'm surprised hardly anyone else has mentioned Wesnoth yet. I last played it over a decade ago, so I'm not sure if it's still as well-known now as it used to be, but it's one of the highest-quality open-source games out there.
It's a turn-based fantasy strategy game that feels like a combination of Advance Wars, Fire Emblem, and D&D. And I suppose it was a lot more unique back in the 2000's when there weren't a dozen indie games out there that fit the same description.
Nethack! It's basically the original roguelike, if you liked shattered pixel dungeons then you'll like nethack. There are also several other open source rogelikes to check out as well... including the original Rogue!
Mindustry and Shattered Pixel Dungeon, I played those a lot of my phone but haven't done so in quite a while! I think both of those are available on desktop Linux too, Shattered Pixel Dungeon even works on my Linux phone.
Yeah, Mindustry is cross platform and available on Linux too. Love mindustry, such an awesome game!
Currently Endless Sky! Although I haven't gotten far, and playing without mods, I love the vibes
Beyond All Reasons. It’s a spiritual successor of Total Annihilation and Supreme Commander using the Spring engine.
It’s also a great game in its own right, especially the various advanced unit positioning and selection features had me amazed. The graphics are good and the performance with many units is finally very good too, after some patches last year (or two years? I don’t remember).
It's pretty basic, but I'm going to say SuperTuxKart as a must if you are into kart racers (especially since I don't know any others).
I also recommend the still in development SuperTux Advance by Kelvin Shadewing. It's similar to just plain old SuperTux but has unique levels and more playable characters that will have different abilities (probably still mostly locked behind debug for them).
Unciv is open source civ5
In terms of games I actually play, Cataclysm: DDA (even if I still suck at it after hundreds of hours).
In terms of technical/visual impressiveness, Veloren.
I haven't played in over a year, but I really spent some hours in Veloren the last time I picked it up!
SuperTuxKart is really good with friends.
Xonotic is one that i would reccomend heavily, and it's an arena shooter
ScummVM works really well in linux, if youre a fan of classic point and click adventure games.
Running on that VM, I really enjoyed Flight of the Amazon Queen a few years back. Warning: it's an oldie containing lots of sexist moments - I'm not sure I would enjoy it as much today.
I've dumped more hours into OpenTTD and Zero-K than I care to think about
I really enjoyed Minedustry. Also, does Katawa Shoujo count?
Tremulous is a free and open source asymmetric team-based first-person shooter with real-time strategy elements. The game features two opposing teams: humans and aliens. Each team must attack the enemy’s base and team members while defending their own base. https://tremulous.net/
Currently downloading but is it still active? Is there still a player base?
If Roblox counts as a game instead of a platform, then I guess Minetest also counts as an open-source game.
Warzone 2100. 3D RTS from the late 90s that was open-sourced after the studio went belly-up. Fantastic game, runs on even ancient hardware.
Edit to add: Forgot to mention it is still receiving updates!
I highly recommend playing Doom with the Crispy Doom source port and the Freedoom data files.
For something more modern, Xonotic is about the best-looking FOSS game out there and an excellent multiplayer arena shooter.
I am on Mobile (aka lazy), so no link. Simutrans for me, beats every other transport sim. The organic growth of cities and industries that happens while you build and optimize your transport systems is one of the many features I like so much.
No one is saying Shattered Pixel Dungeon?
Because I say Shattered Pixel Dungeon.
Cortex Command Community Edition
@sleepybisexual You know what, I could link my articles from a few years ago. It's been a while, so some of newer Open Source games are missing from these lists.
When I did play foss games, I played battle for wesnoth, teeworlds, minetest, super tux csrt and openarena. Lsst one might be dead due to being a mainly multiplayer game.
@sleepybisexual DOOM! The source code is open source, but the assets aren't. So this might be a bit of cheating reply. https://github.com/id-Software/DOOM
There is a complete set of free assets, in the form of Freedoom. Also, the official Steam version is closed-source, so make sure you're getting a free source port. (Most distros have a few in their repos, and Freedoom+GZDoom is also in Flathub.)
I haven't messed with an open source game since early Sauerbraten. I gave up because of the crazy learning curve to git gud.
VVVVVV. It's not GPL though, so technically it's not open source, but source-available.
Note that while the source code is available, the assets is not, so you'll still need to buy the game here: https://store.steampowered.com/app/70300/VVVVVV/
If it's free and open source and it's also software, it can be discussed here. Subcommunity of Technology.
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