Super Galaxy Squadron EX Turbo is probably one of the most insane shoot 'em ups I've ever played and it's now on Linux.
They announced a call for testers only a day ago which was an opt-in beta, but they've already pushed the Linux version out officially. I had a chance to try it after speaking to the publisher who joined our Discord to have a little chat about it.
Note: It will need some 32bit libs installed (list here), however they're porting it to GameMaker Studio 2 so hopefully it will be 64bit in future.
Official feature list:
- Seventeen ships with unique stats and weapons to suit a variety of playstyles
- Six stages of classic shmup action (and savage bosses) in Arcade Mode
- An infinite onslaught to satisfy your scoring itch in Endless Mode
- The supreme timed challenge of Boss Rush Mode
- A range of difficulty options, from calm and newbie-friendly to basically impossible
- Fully voiced cutscenes for the two people looking for a good story
- New mechanics like Overdrive & Focus that help you kill more things and get more points
- A (nearly) complete graphical overhaul
- Still a whole lot of explosions (like you were ever worried)
You can grab it on Steam.