Huge Enemy - Worldbreakers is a rather impressive side-scrolling shoot 'em up that's officially released with Linux support, it also has a demo to try out.
Kingdoms and Castles is a game about building a city and defending it from invaders and dragons, the latest "Beautification Update" update expands your building options even more.
From Orbit is an interesting sounding strategy game that will be coming to Linux next year. Set in deep space, you will be hopping from planet to planet as you try to find your way home.
The day is almost here, Blade Symphony the sword-fighting slash 'em up is getting a big update named Harmonious Prelude and it will release with Linux support on September 27th.
Stellaris is set to have some big changes with the next major update, along with some minor free content added to the Humanoids Species Pack and the Distant Stars Story Pack.
Oxygen Not Included, the excellent survival colony builder from Klei Entertainment now has even more depth to it, as it will allow you to fly your Duplicant people off into space.
Hand of Fate 2 was already a fun game, but the combat was quite simplistic overall. That's not the case now, with the 'Combat Reforged' update that's now out.
Feral Interactive's latest Linux port, Life is Strange: Before the Storm the prequel to the original Life is Strange is set to release for Linux on September 13th.
Lag is always an issue in games, but some games it's much worse than others. The developers behind the FPS games Tannenberg and Verdun have made some steps to improve this.