Fury Unleashed is an action platformer with a seriously good art style from developer Awesome Games Studio, it's out in full now and they added Linux support just before release too.
Unrailed! is a fantastic local and online co-op experience, one where you will be shouting and screaming with laughter at your partner and now you can play it in single-player too.
Indivisible, the action RPG platformer from Lab Zero Games (Skullgirls) can now be played with others in local co-op making it quite a different experience. Plus a New Game Plus mode if you enjoy pain.
StarCrossed, an action-arcade game with a magical girl aesthetic and a cooperative twist has now officially released for Linux shortly after the Windows version became available last month.
Out of Space from developer Behold Studios (Chroma Squad, Galaxy of Pen & Paper) just recently released, and they added Linux support just before leaving Early Access.
Three years after the Kickstarter campaign, the great looking dark sci-fi action RPG Hellpoint from Cradle Games and tinyBuild is confirmed for launch with Linux support on April 16.
Currently free on itch.io while it's not finished, Wild Woods resembles Unrailed! a little in that you're protecting a moving vehicle but it does it in a rather different way.
Developer Indoor Astronaut announced yesterday that their amusing and chaotic track building game Unrailed! now has a Beta available for Linux players to try out.
Overcooked! 2 is no doubt one of the best, most hilarious and most infuriating co-op experiences around all in one. It just got bigger again too, with another great sound DLC out now.
Smith and Winston is a twin-stick shooter made entirely out of really small voxel blocks, it looks awesome and the destruction possible is also pretty amusing.
Wizard of Legend is a really great game, especially when you play it in local co-op I've had an absolutely blast. Now it's even better once you've finished the main wizard trials.
Chronicon might not be a familiar name to some, it's not exactly hugely popular but it does have some of the best action-RPG gameplay available on Linux.
With thanks to Team17 sending over a copy, I checked out the chaotic cooking game Overcooked! 2. Coming in totally fresh, since I had never played the original.