Airships: Lost Flotilla is a really good auto-shooter taking elements from survivor-like bullet hells and it just had a big free content expansion. It has Native Linux support and is Steam Deck Verified.
Like other games inspired by the mechanics from Vampire Survivors, you pick a character (in this case, a ship) and go through waves of enemies while you keep upgrading. Airships: Lost Flotilla is one of the more unique in the list though with the path progression system where you pick different nodes, each a different location to fight through with unique bonuses to acquire.
The latest update adds in six new airships to pilot, five new enemy factions with their own unique set of enemies to shoot down, lots of new weapons and new captains to pick to mixup your play-through. Check out the update trailer:
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