I still think Prison Architect is a bit of a genius idea for a game, not only that but the game is actually quite good. The developers didn't stop after it quit early access either with update number 1.
The Last Federation, a strategy game about creating an interplanetary federation, has received its second expansion which brings new technologies and a new game mode.
Sang-Froid Developer Artifice Studios has released their outlandish space RTS 'Conflicks: Revolutionary Space Battles' on Steam, and a multiplayer demo is also available for Linux.
The developers themselves emailed both Age of Fear: The Undead King & Age of Fear 2: The Chaos Lord in for me to take a look at. They told me the games don't look like much, but offer a lot, and they were right.
Football fans rejoice! We have a day one release of Football Manager 2016 for Linux & SteamOS. It's a very popular game series, and great to see another on Linux.
Legends of Eisenwald an adventure game with tactical battles, RPG and strategy elements that was funded on Kickstarter. They wanted to do a Linux release, but they didn't hit the goal to do it right away, and now due to finances it's on hold.
Torment: Tides of Numenera is an upcoming crowdfunded RPG from veteran developers inXile Entertainment set in the Numenera universe, and a spiritual successor to Planescape: Torment.
Wyrmsun is yet another game we totally missed, mainly due to it not appearing in the SteamOS + Linux new releases. Valve really need to fix games showing up there if they add a Linux version to an existing release later on.
Rise: Battle Lines is a quick and accessible multiplayer-focused battle game that delivers meaty strategy in a bite-size format. It's just been released on Linux (via Steam) for the princely sum of $4.99/£3.99!
Ashes of the Singularity looks like an awesome RTS game to try, and the developers have confirmed again they want to do Linux, but they are waiting for Vulkan.
As a big fan of the XCOM games, I was really excited to see what the original designer could do with his next game. Chaos Reborn is an interesting take on the fantasy turn based strategy genre.
I forget that Natural Selection 2 is on Linux, mainly due to the dying player base and how dog slow it was to load, but it seems they are finally taking steps to improve that part of it.
If you have fond memories of the setting of Darkwatch, or you've always wished XCOM featured cowboys and demons instead of aliens, consider yourself lucky.