Quoting: CorbenA game which wasn't mentioned here and will probably be never ported:
Evolve.
The stealth announcement was during the Steam Universe announcement, but was never officially confirmed. We had some steamdb movement, but there didn't happen anything for a long time. So it will probably also never happen.

Another game I would like to see ported, but the signs aren't looking good:
Gas Guzzlers Extreme.

And there are some games I wish would be ported... like Doom or Elite: Dangerous... the only hope is wine, but as e.g. with Doom, we know it's not working due to DRM, though the engine would be perfect as it's using OpenGL now or Vulkan in the future.

Back in December 0f 2014 I emailed the developer behind Gas Guzzlers asking about Linux and they said the decision belonged to the publisher and that there were plans to release a Linux version but that they were not working on it currently. Didn't sound good then and I haven't seen any progress or news to say otherwise.

Last I heard, it was few months ago. Linux version of Gas Guzzlers Extreme should be in progress now.

Gas Guzzlers Extreme looks like it is going to come to Linux, porting starts soon

I think that I never will see in Linux, Rome II, Darksiders and Project Cars. I hope to be wrong. My brother owns Rome II. He bought it to play it with wine, but the game don't runs very well. He have the hope of a native port.

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Quoting: PublicNuisanceIf I want a Linux copy I have to go to Steam and shell out for a DRM copy. DRM free users get shafted with only getting the Windows version. I could make a whole thread on that sad practice.

I was curious about that practice, too, thinking that DRMfree would be something that especially would appeal to Linux users, so I brought that up in a discussion with one of the Kalypso guys since they only have a Linux version of GA:M available on steam but not on GOG while the windows versions are on both. He said that they have to do it that way because they don't do Multiplayer/User Management themselves, so they need steam or gog galaxy for that and it is not available on Linux.

Until now Linux gaming has been pretty poor, but just look at what we have now, more and more triple A games are being ported. To port a game over to Linux, you first need the publishers permission, then you have to throw money at your project, to get it going. Feral for instance, must have to go for loads of meetings and spend hours and hours coding, testing, getting sponsors to fund them and so forth. Well I guess it's done this way? I maybe wrong, but when you look into the work that goes into actually porting a game, it must get pretty complicated.

There are dozens of games I would like to see come to Linux from The Resident Evil series, Metal Gear Solid Twin Snakes the Nintendo GameCube remake, GTA 3, Vice City, San Andreas, GTA 4, GTA 5, Rise Of The Tomb Raider. The list is endless, but until the day that Linux gets the recognition and the understanding from big gaming giants that Linux is a fantastic system for playing games on too, as well as the Mac or Windows are, then we will never see the big games being ported. Capcom, Rockstar, Konami are all big game companies, that will probably never say hello to Linux, unless Linux Gamers pay for their games, which we are having to do either through Steam or Feral.

Linux is probably the most powerful OS on the planet, but while the big players are out there Microsoft who can throw their money at anything or everything and things work nearly first time for them, but here in Linux it is open source and when you say Open Source to a giant company, they run a mile. Open Source software has come along way, since it's early days, as the programming has gotten better and better. There will one day, not in my life time, but one day when all games will be released on every OS platform.

I love gaming on my Linux machine, simply because it is not constantly running things in the background, like the Anti-Virus that keeps spinning in Windows. I'm currently playing Tomb Raider 2013 the Feral Port and I must say Feral have done a fantastic job with the port. I'm using the 361.42 driver, as my Nvidia card is only a GeForce 640 with 2GB of Ram and the OS I'm using is Ubuntu Mate 16.04. I had some display issues at first, but now that Feral and Steam have updated it, it runs superbly. Tomb Raider 2013 is a stunning looking game and is my all time favorite Tomb Raider game.

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makes me sad the Witcher 3 isn't coming through. I sinned and bought it anyway for Windows since its future for Linux looked bleak. I remain hopeful it'll come out, but I doubt it.

Just couldn't resist Geralt and his grand adventures.

Starting to wonder about an update to ARMA3 port. They are soon to release APEX expansion with 1.60+ and the Linux port is still on 1.54 without any battleye (which ARK has working btw).

BIS is basically 100% radio silent with any potential update, thought maybe they have no control of it due to being ported by 3rd party dev, whom may be waiting for official APEX.. Lots of speculation, no information :(

Street Fighter V