Gaming

Beyond All Reason

https://www.beyondallreason.info/

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

Cataclysm Dark Days Ahead has been mentioned so I'll add OpenMW to the thread. It's a open source engine rewrite of Morrowind and requires the base game to run Morrowind but it has the potential to be used to create new games and the devs are looking to expand it to allow the creation of ARPGs as well.

Another worthy mention is Endless Sky, it's an open source game inspired by the classic space trading and combat game Escape Velocity.

Tux Racer. Hands down.

Mindustry is a really fun automation/tower defense game

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.

I will say that 0 A.D. and veloren are my favourites!

Dungeon Crawl Stone Soup Love this traditional roguelike!

Pixel Dungeon! Great rogue like mobile game

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.

Teeworlds. There are some great community made modes for it like FNG and DDrace. Be sure to download it from ddnet.tw to access to extra features created by the community.

Battle of Wesnoth. Haven't played it in a while, but I remember spending hours playing that at one point.

Shattered Pixel Dungeon ! And its origin, Pixel Dungeon.

A really nice rogue-like, among the best Android games I know, it’s still fun after all those years and very actively developed !

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

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)

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

https://github.com/open-duelyst/duelyst

Duelyst was a very popular online card game that shutdown around 3 years ago. The developers have recently released it into the public domain (via CC0 license).

You can completely selfhost a private instance (repo has a good straight forward guide)

There is a public instance available to try https://duelyst.org/. Though it might be pretty barren.

There is also a closed fork which should have a more active userbase https://duelyst2.com/, the game rules are a little different (draw 2 vs draw1), but should have more users to get a feeling for the game.

The game in a nutshell is basically Hearthstone on a chessboard. It’s very fun and approachable and in my opinion one of the best cardgames right next to MagicTCG :). Hopefully the community for it will grow more and we can have a sort of second renaissance for it :)

If you like RTS games similar to Total Annihilation, you should definitely check out Beyond All Reason, it's gorgeous and fun: https://www.beyondallreason.info/

Beyond All Reason is AMAZING. I can't say enough about it. Its my favourite game, and totally annihilates (!) the competition.

Though I guess the competition is pretty small for large scale RTS. Maybe:

• Total Annihilation
• Supreme Commander
• Ashes of the Singularity
• Sins of the Solar Empire (sorta)

BAR has fixed all the UI/UX problem, scales well, has a big community, is free, fun, and super deep and complex.

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.

OpenTTD is my drug. I'm addicted

Pokemon Emerald 😉

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

OpenTTD is good

Warzone 2100 is an RTS from 1999 that went open source at some point and can be played on just about anything. It's unit design functionality is really cool and I'm a sucker for post-apocalyptic worlds.

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

Mindustry is an awesome strategy game that combines Factorio with tower defense.

Sonic Robo Blast 2 Kart (ridiculous name I know) is one of the most underrated games ever. It's a super polished, high quality Kart game with an insane amount of mods and maps. The online isn't that populated but the singleplayer time trial is TONS of fun. If you like hunting for medals, it can be a pretty deep rabbit hole. There's a sequel in development but no release date.

GzDoom is the most popular Doom source port and there's a practically infinite amount of user generated content. If you don't know where to start I highly recommend Doom: The Golden Souls Remastered and Castlevania: Simon's Destiny. They're good enough to be premium games.

There are a few open source game projects I follow. I suppose the most famous one is the Freespace 2 source code project. Although it didn't start open source, the original devs open-sourced it later. It has great support, and a great modding launcher called Knossos. To play the game, even with the source code, you either need the original disks or a copy of the installer from GoG, but it's really cheap. Getting it working on Windows is pretty easy, but Linux is only slightly more complicated. (Fortunately, there's a new launcher that makes it way easier).

If you're interested, let me know.

OpenTTD is a great open source clone of the transport tycoon game. And boohu is an awesome ASCII coffeebreak roguelike.

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

Some great games already on here, but wanted to share some love for VVVVVV which released its source a few years ago.

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?

For me it's CDDA, a quite realistic and deep apocalyptic survival game with very frequent updates(on the experimental branch)

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

Tremulous - The game was so fun back then (like 10 years ago ?) I guess it's a dead game now.

There's not a whole lot of activity around it these days, but Zelda Classic is an engine for Zelda 1 with a number of additions and improvements, that allows for custom maps, tilesets, scripts, items, enemies, etc. etc.

I've whiled away an unreasonable amount of time on quests that are on par mechanically and quality-wise with Link's Awakening and the Oracle games. Shame I can't get the tarball to work properly on Steam Deck, it's a great fit for that hardware.

Oh I am saving this post! It's a goldmine

Simutrans. It's old but really good. It's really easy to lose 10h or so in it before you notice the time.

Cube 2 Sauerbraten is pretty good! Free arena shooter with built-in level editor

Veloren is inspired by games such as Cube World, Legend of Zelda: Breath of the Wild, Dwarf Fortress and Minecraft.

You can play single player or multi-player, standalone or use an online server, or even host your own server in a Docker container, or on a Raspberry Pi. Plenty of options!

You start by creating your character, you can collect items for your inventory, you can craft items, there are weapons and combat, you develop skills, can tame creatures, you can trade with merchants, you can socialise, and lost more. There is no single, specific goal or focus, and the idea is to keep exploring and have adventures.

The game is community driven and actually updates quite regularly.

It is clearly no clone of Minecraft. It is fun and adventure!

See https://veloren.net/