List of other multi-platform games - free or open source.

[Oathbreaker]

http://www.reddit.com/r/gaming/comments ... source_or/

Post download webpage link or description/video link with a very brief idea of what the game is about. I'm also an old fart who can remember when the original Rogue with coloured ASCII graphics was cutting edge, so my list will be mostly old guy stuff. OLD GUYS RULE. Elite. Wing Commander. Bubble Bobble. Gunship.

2-D Top down space shooter/trader.
http://blog.naev.org/downloads/ "Naev" - Escape Velocity Nova clone, beta.

3-D Space combat simulator/trader.
http://vegastrike.sourceforge.net/getfiles/ "Vega Strike" Wing Commander-type. Open Source 3D Action-Space-Sim that lets you trade, fight, and explore in a vast universe. Under development.
http://privateer.sourceforge.net/files.shtml "Wing Commander: Privateer Gemini Gold" 3-D space combat simulator.
http://www.oolite.org/ Oolite is a space sim game, inspired by Elite, powered by Objective-C and OpenGL, and designed as a small game that is easy for users to pick up, modify and expand upon. Almost every aspect of the game can be changed by using simple, free graphics packages and text editors.

Roguelike
http://www.bay12games.com/dwarves/ "Dwarven Fortress" - Roguelike greatly expanded, with Adventurer mode and RTS resource-management. Keep in mind there's plenty of graphical & other mods.
http://te4.org/download "Tales of Maj'Eyal: Age of Ascendancy" Topdown tactical RPG roguelike game and game engine.
http://rephial.org/ Angband is a roguelike free, single-player dungeon exploration game.
http://crawl.develz.org/wordpress/downloads Dungeon Crawl Stone Soup

Casual/puzzle/platform
http://www.frozen-bubble.org/downloads/ "Frozen Bubble" - Bubble Bobble clone. I have yet to find the supposedly working Mac version download.
http://www.secretmaryo.org/index.php?pa ... &sid=?sid= Secret Maryo Chronicles is an Open Source two-dimensional platform game with a design similar to classic computer games. SMC has computer support to a great degree by using an accelerated Open Graphics Library for the best possible graphic design and stock performance.

Tactical turn-based
http://ufoai.ninex.info/wiki/index.php/Download "UFO: Alien Invasion" - X-Com UFO series clone, check forums if you can't get it to start on your platform (I had issues on Mac). Beta.
Jagged Alliance 2 may be workable on different systems, google is your friend but you'll have to work the magic and do some hunting. Go get 'em, tiger.
http://www.megamek.info/downloads MegaMek is an unofficial, online version of the Classic BattleTech board game. MegaMek is open source, free software. It is licenced under the GPL.
If you can find me a simple, easy way to get the old WH40K: Chaos Gate working on a Mac I'll buy you a case of beer.
Silent Storm anyone?

Strategy
http://www.scorched3d.co.uk/ Scorched 3D is a modernization of the classic DOS game Scorched Earth "The Mother Of All Games".
http://www.freecol.org/download.html FreeCol is a turn-based strategy game based on the old game Colonization, and similar to Civilization. The objective of the game is to create an independent nation.
http://freeciv.wikia.com/ Freeciv is a Free and Open Source empire-building strategy game inspired by the history of human civilization. The game commences in prehistory and your mission is to lead your tribe from the stone age to the space age...
http://www.freeorion.org/index.php/Download FreeOrion is a free, open source, turn-based space empire and galactic conquest (4X) computer game designed and built by the FreeOrion project. FreeOrion is inspired by the tradition of the Master of Orion. Tactical combat seems to be in the works. See also http://freeorion.org/index.php/Space_Strategy_Games for a list of similar games. See http://www.youtube.com/user/freeorionorg#p/u for a VERY snazzy-looking space combat preview toward the end of the promotional video.

Racing/arcade
http://armagetronad.net/downloads.php Armagetron Advanced - "A Tron clone in 3D." http://youtu.be/wKnTOYxtMeg is a pretty kickass trailer for it.

RPG
http://exult.sourceforge.net/ Exult is a project to recreate Ultima 7 for modern operating systems, using the game's original plot, data, and graphics files.
http://xu4.sourceforge.net/ XU4 is a remake of the computer game Ultima IV.
http://www.wesnoth.org/ The Battle for Wesnoth is a Free, turn-based tactical strategy game with a high fantasy theme, featuring both single-player, and online/hotseat multiplayer combat.
http://www.allacrost.org/download Hero of Allacrost is a single player 2D rpg inspired by classic console RPGs. Explore rich environments, solve challenging dungeon puzzles, and fight strategic battles in an active-time based system. Free open-source software and is available across several platforms including Windows, OS X, Linux, and FreeBSD.

FPS
I'm not big into FPS (except Tactical Ops back in the day), so feel free to suggest your favourites. If you're dying for something, try http://www.truecombatelite.com/ which is what I found just browsing around.

Other
http://www.vassalengine.org/ Vassal is a game engine for building and playing online adaptations of board games and card games. Play live on the Internet or by email. Vassal runs on all platforms, and is free, open-source software. Google will find you the old Warhammer 40,000 module for it, called "v40k".
http://en.wikipedia.org/wiki/List_of_fr ... ideo_games
http://en.wikipedia.org/wiki/List_of_open_source_games
http://freshmeat.net/tags/games

Not included itt:
Free-to-play online stuff with a pay-for-perks business model like "The Lacuna Expanse" etc.
Let's be nice and inclusive about this, keep the hate in some other thread. (I'm on a Mac but my next computer won't be as I no longer need that one application that I could only get via Mac OS X.) If you find or have something that's just $1 or $2 then feel free to contribute a link, as well. I have yet to play all the above, so let me know if something doesn't work.

[tonycro]

nice one - thanks

[DaddyHoggy]

For a good FPS try Urban Terror. It used to be a total conversion for v1.32 of Quake III Arena, but since the ioQuake Engine was released it's now standalone.

(It'll even run on Linux with a bit of jiggery-pokery - although if you run Linux you could try OpenArena)

http://www.urbanterror.info/home/

http://linux.softpedia.com/get/GAMES-EN ... 7341.shtml

[Selezen]

Urban Terror's not half bad, actually. it's one of the few free FPS games that allows bots with minimal tweaking.

We used to play it at lunchtimes at work until it became too dangerous. Sitting shouting death threats at each other when visitors from head office were around was detrimental to our careers...

[DaddyHoggy]

Urban Terror's not half bad, actually. it's one of the few free FPS games that allows bots with minimal tweaking.

We used to play it at lunchtimes at work until it became too dangerous. Sitting shouting death threats at each other when visitors from head office were around was detrimental to our careers...

We use it to stress our lab's network post student exercise - 32 students blowing the crap out of each other with G36s is quite amusing...

[Oathbreaker]

Oh, and if someone finds me a multi-platform or Mac or open source version of Frontier's Virus and V2000, please please PM me or post here.

[Wyvern Mommy]

if the topic title wasn't "games", i would add flightgear to the list

[Ganelon]

I would note that "Wing Commander: Privateer Gemini Gold" is a development off the "Vega Strike" engine. But it is significantly different in gameplay and storylines and touches like cut-scenes that I would agree it should have the separate entry. Both are very good, though I prefer VS.

For FPS multiplatform, there's also:

Sauerbraten is fast and has at least one space/sci-fi scenario in the single player mode
http://sauerbraten.org/

Alien Arena is manic run-and-gun action with some really cool scenery/locations.
http://red.planetarena.org/

I haven't tried them under windows or mac, but they have downloads for them. They run quite well on Linux/Ubuntu.

I would also agree with Wyvern regarding FlightGear, since it's a simulator rather than a proper game. Fun, just a different sort of fun.

[Commander Wilmot]

Another roguelike though it doesn't seem like it at first:
Transcendence
It is easily modifiable like Oolite though they don't provide an add-ons folder or any instructions on what to name the folder you need to add the mods into.

Shooters:
Black Shades
Runs on Mac OS X and Windows, I don't know whether Wine can run it on Linux.

Tactical Games/Roguelike
Alien Assault

edit: never mind the last one, it doesn't run on anything but windows. Same for Transcedence, huh, could have sworn that it ran on multiple OSes, sorry.

[Commander Wilmot]

One other Roguelike:
Ascii Sector
this one really is for Mac, Linux, and Windows.

[Commander Wilmot]

Shooter:
Assault Cube
It started as a mod off the original Cube game. Assault Cube is still around as it's own game even though Cube has been replaced by Cube 2 aka Sauerbraten.

edit: Red eclipse is finally out. It is a total conversion of Cube 2.